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[Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Purchase consideration Business Combination, Consideration Transferred Purchase Price Allocation Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract] Current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Non-current deferred tax asset Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets Noncurrent Non-current tangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Tangible Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Tangible Assets Acquired intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Total identifiable net assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Goodwill Goodwill Net assets acquired Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Goodwill expected to be tax deductible Business Acquisition, Goodwill, Expected Tax Deductible Amount Document And Entity Information [Abstract] Document And Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Amendment Flag Amendment Flag Entity Common Stock, Shares 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from Lines of Credit Repayments of debt Repayments of Debt Long-term debt Long-term Debt, Gross Debt issuance costs Debt Issuance Costs, Net Payments of Debt Issuance Costs Payments of Debt Issuance Costs Write off of unamortized debt issuance costs Write off of Deferred Debt Issuance Cost Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2004 Stock Option Plan 2004 Stock Option Plan [Member] 2004 Stock Option Plan [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Options grated to date (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of 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Earnings Per Share, Amount Income tax benefit from reorganization Effective Income Tax Rate Reconciliation, Internal Reorganization, Amount Effective Income Tax Rate Reconciliation, Internal Reorganization, Amount Income Tax Disclosure [Abstract] INCOME TAXES Income Tax Disclosure [Text Block] Hightail, Inc Hightail, Inc [Member] Hightail, Inc [Member] Guidance Software Inc. Guidance Software Inc. [Member] Guidance Software Inc. [Member] Covisint Corporation Covisint Corporation [Member] Covisint Corporation [Member] ECD Business ECD Business [Member] ECD Business [Member] Recommind Inc Recommind Inc [Member] Recommind Inc. [Member] ANXeBusiness Corp. ANXeBusiness Corp [Member] ANXeBusiness Corp [Member] CEM Business CEM Business [Member] CEM Business [Member] Schedule of Business Acquisitions, by Acquisition Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Recognized Identified Assets Acquired and Liabilities Assumed Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Segment Reporting [Abstract] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] Canada CANADA United States UNITED STATES United Kingdom UNITED KINGDOM Germany GERMANY Rest of Europe Rest of Europe [Member] Rest of Europe[Member] All other countries All Other Countries [Member] All other countries [Member] Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Total Long-Lived Assets Accounting Policies [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2014-09 Accounting Standards Update 2014-09 [Member] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Difference between Revenue Guidance in Effect before and after Topic 606 Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Forecast Scenario, Forecast [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Total estimated net adjustment to retained earnings Retained Earnings (Accumulated Deficit) Decrease in deferred revenues Contract with Customer, Liability Decrease in deferred implementation costs Deferred Costs Increase of capitalized sales commission costs Capitalized Contract Cost, Net Increase in contract assets Contract with Customer, Asset, Net Increase in net deferred tax liabilities Cumulative Effect on Retained Earnings, Tax Restructuring, Settlement and Impairment Provisions [Abstract] SPECIAL CHARGES (RECOVERIES) Restructuring, Impairment, and Other Activities Disclosure [Text Block] Domestic income (loss) Income (Loss) from Continuing Operations before Income Taxes, Domestic Foreign income Income (Loss) from Continuing Operations before Income Taxes, Foreign Income before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS Significant Accounting Policies [Text Block] Long-term deferred tax liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Other liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Acquired receivables, fair value Business Combination, Acquired Receivable, Fair Value Acquired receivables, gross contractual amount Business Combination, Acquired Receivables, Gross Contractual Amount Acquired receivables, estimated uncollectible Business Combination, Acquired Receivables, Estimated Uncollectible Commitments and Contingencies Disclosure [Abstract] Long term debt obligations Maturities of Long-term Debt and Capital Lease Obligations [Abstract] Total Long-term Debt and Capital Lease Obligations July 1, 2018— June 30, 2019 Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year July 1, 2019— June 30, 2021 Long-term Debt, Maturing in Years Two and Three July 1, 2021— June 30, 2023 Long-term Debt, Maturing in Years Four and Five July 1, 2023 and beyond Long-term Debt, Maturities, Repayments of Principal after Year Five Operating lease obligations Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Total Operating Leases, Future Minimum Payments Due July 1, 2018— June 30, 2019 Operating Leases, Future Minimum Payments, Remainder of Fiscal Year July 1, 2019— June 30, 2021 Operating Leases, Future Minimum Payments, Due in Two and Three Years July 1, 2021— June 30, 2023 Operating Leases, Future Minimum Payments, Due in Four and Five Years July 1, 2023 and beyond Operating Leases, Future Minimum Payments, Due Thereafter Purchase obligations Purchase Obligation, Fiscal Year Maturity [Abstract] Total Recorded Unconditional Purchase Obligation July 1, 2018— June 30, 2019 Recorded Unconditional Purchase Obligation, Due in Remainder of Fiscal Year July 1, 2019— June 30, 2021 Recorded Unconditional Purchase Obligation Due in Second and Third Year Recorded Unconditional Purchase Obligation Due in Second and Third Year July 1, 2021— June 30, 2023 Recorded Unconditional Purchase Obligation Due in Fourth and Fifth Years Recorded Unconditional Purchase Obligation Due in Fourth and Fifth Years July 1, 2023 and beyond Recorded Unconditional Purchase Obligation Due after Fifth Year Total payments due between Contractual Obligation, Fiscal Year Maturity [Abstract] Total Contractual Obligation July 1, 2018— June 30, 2019 Contractual Obligation, Future Minimum Payments Due, Remainder of Fiscal Year July 1, 2019— June 30, 2021 Contractual Obligation, Due in Second and Third Year July 1, 2021— June 30, 2023 Contractual Obligation, Due in Fourth and Fifth Year July 1, 2023 and beyond Contractual Obligation, Due after Fifth Year 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Reconciliation, Prior Year Income Taxes, Increase (Decrease), Amount Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Increase (Decrease), Amount Decrease from reversal of reserves Effective Income Tax Rate Reconciliation, Effect of Changes in Unrecognized Tax Benefits, Increase (Decrease), Amount Effective Income Tax Rate Reconciliation, Effect of Changes in Unrecognized Tax Benefits, Increase (Decrease), Amount Decrease in deferred tax assets valuation allowance, amount Effective Income Tax Rate Reconciliation, Amortization of Deferred Charges, Increase (Decrease), Amount Effective Income Tax Rate Reconciliation, Amortization of Deferred Charges, Increase (Decrease), Amount Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Domestic Tax Authority Domestic Tax Authority [Member] Foreign Tax Authority Foreign Tax Authority [Member] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Operating loss carryforwards Operating Loss Carryforwards Deferred tax assets, operating loss carryforwards, not subject to expiration Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration Investment tax credit Investment Tax Credit Unrecognized tax benefits of deferred tax assets offset by valuation allowance Unrecognized Tax Benefits Of Deferred Tax Assets Offset by Valuation Allowance Unrecognized Tax Benefits Of Deferred Tax Assets Offset by Valuation Allowance Net unrecognized tax benefit excluding portion offset by valuation allowance Net Unrecognized Tax Benefit Excluding Portion Offset by Valuation Allowance Net Unrecognized Tax Benefit Excluding Portion Offset by Valuation Allowance Increase resulting from prior period tax positions, subject to recovery as an indemnified asset Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions, Subject to Recovery as an Indemnified Asset Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions, Subject to Recovery as an Indemnified Asset Possible decrease in tax expense in next 12 months Decrease in Unrecognized Tax Benefits is Reasonably Possible Taxes paid on cash distribution Taxes Paid on Cash Distribution Taxes Paid on Cash Distribution Adjustment of deferred tax assets and liabilities Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability Impact of changes in US tax legislation, as a percent Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Loss Contingencies [Table] Loss Contingencies [Table] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Income Tax Authority, Name [Domain] Internal Revenue Service (IRS) Internal Revenue Service (IRS) [Member] Canada Revenue Agency (CRA) Canada Revenue Agency [Member] Tax Period [Axis] Tax Period [Axis] Tax Period [Domain] Tax Period [Domain] Tax Year 2010 Tax Year 2010 [Member] Tax Year 2012 Tax Year 2012 [Member] Tax Year 2013 Tax Year 2013 [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] GXS Group, Inc. GXS Group, Inc. [Member] GXS Group, Inc. [Member] GXS India GXS India [Member] GXS India [Member] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Municipality of Sao Paulo Municipality of Sao Paulo [Member] Municipality of Sao Paulo [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Estimated amount of loss resulting from an adverse tax position Income Tax Examination, Estimate of Possible Loss Income tax examination, tax Income Tax Examination, Estimate Of Possible Loss, Tax Income Tax Examination, Estimate of Possible Loss, Tax Income tax examination, penalties Income Tax Examination, Estimate Of Possible Loss, Penalties Income Tax Examination, Estimate of Possible Loss, Penalties Income tax examination, interest Income Tax Examination, Estimate Of Possible Loss, Interest Income Tax Examination, Estimate of Possible Loss, Interest Income tax examination, change in liability Income Tax Examination, Increase (Decrease) in Liability from Prior Year Income tax examination, penalties and interest Income Tax Examination, Estimate Of Possible Loss, Penalties And Interest Income Tax Examination, Estimate Of Possible Loss, Penalties And Interest Additional tax expense, as a percent Income Tax, Penalty Rate Income Tax, Penalty Rate Income tax examination, estimate of increase to taxable income Income Tax Examination, Estimate of Increase to Taxable Income Income Tax Examination, Estimate of Increase to Taxable Income Payments for legal settlements Payments for Legal Settlements Loss contingency accrual Loss Contingency Accrual Supplemental Cash Flow Information [Abstract] Supplemental Disclosure of Cash Flow Information Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Restructuring Plan [Axis] Restructuring Plan [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] Fiscal 2018 Restructuring Plan Fiscal 2018 Restructuring Plan [Member] Fiscal 2018 Restructuring Plan [Member] Fiscal 2017 Restructuring Plan Fiscal 2017 Restructuring Plan [Member] Fiscal 2017 Restructuring Plan [Member] Restructuring Plans prior to Fiscal 2017 Restructuring Plan Restructuring Plans prior to Fiscal 2017 Restructuring Plan [Member] Restructuring Plans prior to Fiscal 2017 Restructuring Plan [Member] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Special charges Restructuring Charges Acquisition-related costs Business Combination, Acquisition Related Costs Other charges (recoveries) Restructuring Charges (Recoveries), Other Restructuring Charges (Recoveries), Other Total Restructuring, Settlement and Impairment Provisions Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Subsequent Event [Line Items] Subsequent Event [Line Items] Dividends declared per common share (in dollars per share) Common Stock, Dividends, Per Share, Declared Retirement Benefits [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Pension Plan Pension Plan [Member] Other plans Other Pension, Postretirement and Supplemental Plans [Member] Retirement Plan Name [Axis] Retirement Plan Name [Axis] Retirement Plan Name [Domain] Retirement Plan Name [Domain] CDT defined benefit plan CDT [Member] CDT [Member] GXS GER defined benefit plan GXS Germany [Member] GXS Germany [Member] GXS PHP defined benefit plan GXS Philippine [Member] GXS Philippine [Member] Assumptions: Defined Benefit Plan Disclosure [Line Items] Total benefit obligation Liability, Defined Benefit Plan Current portion of benefit obligation Liability, Defined Benefit Plan, Current Non-current portion of benefit obligation Liability, Defined Benefit Plan, Noncurrent CDT GXS GER GXS PHP Defined Benefit Plan, Employee Age Group [Axis] Defined Benefit Plan, Employee Age Group [Axis] Defined Benefit Plan, Employee Age Group [Axis] Defined Benefit Plan, Employee Age Group [Domain] Defined Benefit Plan Employee Age Group [Domain] Defined Benefit Plan, Employee Age Group [Domain] to age 20 Employee Age Up to 20 [Member] Employee Age Up to 20 [Member] to age 25 Employee Age Up to 25 [Member] Employee Age Up to 25 [Member] to age 30 Employee Age Up To Thirty [Member] Employee Age Up To Thirty [Member] to age 35 Employee Age Up To Thirty Five [Member] Employee Age Up To Thirty Five [Member] to age 40 Employee Age Up To Forty [Member] Employee Age Up To Forty [Member] to age 45 Employee Age Up To Forty Five [Member] Employee Age Up To Forty Five[Member] to age 50 Employee Age Up To Fifty [Member] Employee Age Up To Fifty [Member] from age 51 Employee Age Above Fifty One [Member] Employee Age Above Fifty One [Member] Salary increases Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Pension increases Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Rate Of Pension Increase Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Rate Of Pension Increase Discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Normal retirement age Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Retirement Age Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Retirement Age Employee fluctuation rate Employee Fluctuation Rate Employee Fluctuation Rate Other Assets, Noncurrent Disclosure [Abstract] Components of Other Assets Schedule of Other Assets [Table Text Block] Schedule of Intercompany Foreign Currency Balance [Table] Schedule of Intercompany Foreign Currency Balance [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Other Income (Expense) Other Nonoperating Income (Expense) [Member] Intercompany Foreign Currency Balance [Line Items] Intercompany Foreign Currency Balance [Line Items] Transactional foreign currency gains (losses) Foreign Currency Transaction Gain (Loss), before Tax Amount held back and unpaid Business Combination, Contingent Consideration, Liability Liabilities assumed 2019 Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months 2020 Defined Benefit Plan, Expected Future Benefit Payment, Year Two 2021 Defined Benefit Plan, Expected Future Benefit Payment, Year Three 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Four 2023 Defined Benefit Plan, Expected Future Benefit Payment, Year Five 2024 to 2028 Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter Total Defined Benefit Plan Expected Future Benefit Payments Total Defined Benefit Plan Expected Future Benefit Payments Total Deferred tax assets Deferred Tax Assets, Tax Deferred Expense [Abstract] Non-capital loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards Capital loss carryforwards Deferred Tax Assets, Other Loss Carryforwards Undeducted scientific research and development expenses Deferred Tax Assets Research and Development Deferred Tax Assets Research and Development Depreciation and amortization Deferred Tax Assets, Property, Plant and Equipment Restructuring costs and other reserves Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Restructuring Charges Deferred revenue Deferred Tax Assets, Deferred Income Other Deferred Tax Assets, Other Total deferred tax asset Deferred Tax Assets, Gross Valuation Allowance Deferred Tax Assets, Valuation Allowance Deferred tax liabilities Deferred Tax Liabilities, Deferred Expense [Abstract] Scientific research and development tax credits Deferred Tax Liabilities, Deferred Expense, Capitalized Research and Development Costs Acquired intangibles Deferred Tax Liabilities, Intangible Assets Other Deferred Tax Liabilities, Other Deferred tax liabilities Deferred Tax Liabilities, Net Net deferred tax asset Deferred Tax Assets, Net Comprised of: Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Classification [Abstract] Long-term assets Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Long-term liabilities Deferred Tax Liabilities, Net, Noncurrent LONG-TERM DEBT Long-term Debt [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] BASIS OF PRESENTATION Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Accounts Payable and Accrued Liabilities [Abstract] Accounts payable—trade Accounts Payable, Current Accrued salaries and commissions Employee-related Liabilities, Current Accrued liabilities Accrued Liabilities, Current Accrued interest on Senior Notes Accrued Interest on Senior Unsecured Fixed Rate Notes Accrued Interest on Senior Unsecured Fixed Rate Notes Amounts payable in respect of restructuring and other Special charges Restructuring Reserve, Current Asset retirement obligations Asset Retirement Obligation, Current Total Current Accounts Payable And Accrued Liabilities Plus Other Accruals Current Accounts Payable And Accrued Liabilities Plus Other Accruals Deferred revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue Deferred revenue adjustment Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Revenue Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Revenue SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] Cost Available-for-sale Securities, Amortized Cost Basis Gross Unrealized Gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized (Losses) Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Estimated Fair Value Available-for-sale Securities Schedule of Current Liabilities Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Schedule of Long-Term Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Schedule of Restructuring Reserve Restructuring and Related Costs [Table Text Block] ACQUISITIONS Business Combination Disclosure [Text Block] Amounts payable in respect of restructuring and other Special charges Restructuring Reserve, Noncurrent Other accrued liabilities Other Accrued Liabilities, Noncurrent Asset retirement obligations Asset Retirement Obligations, Noncurrent Total Non current Accounts Payable And Accrued Liabilities Plus Other Accruals Non current Accounts Payable And Accrued Liabilities Plus Other Accruals Property, Plant and Equipment [Abstract] PROPERTY AND EQUIPMENT Property, Plant and Equipment Disclosure [Text Block] Contractual Obligations Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block] Customer Assets Technology Assets Current income taxes (recoveries): Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Domestic Current Federal Tax Expense (Benefit) Foreign Current Foreign Tax Expense (Benefit) Total Current Income Tax Expense (Benefit) Deferred income taxes (recoveries): Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Domestic Deferred Federal Income Tax Expense (Benefit) Foreign Deferred Foreign Income Tax Expense (Benefit) Total Deferred Income Tax Expense (Benefit) Provision for (recovery of) income taxes Income Tax Expense (Benefit) Statement of Comprehensive Income [Abstract] Net income for the period Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Other comprehensive income (loss)—net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Net foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Unrealized gain (loss) on cash flow hedges: Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract] Unrealized gain (loss) - net of tax expense (recovery) effect of ($171), $34 and ($928) for the year ended June 30, 2018, 2017 and 2016, respectively Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax (Gain) loss reclassified into net income - net of tax (expense) recovery effect of ($489), $67 and $1,065 for the year ended June 30, 2018, 2017 and 2016, respectively Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax Actuarial gain (loss) relating to defined benefit pension plans: Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax [Abstract] Actuarial gain (loss) - net of tax expense (recovery) effect of ($1,846), $840 and ($1,612) for the year ended June 30, 2018, 2017 and 2016, respectively Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax Amortization of actuarial (gain) loss into net income - net of tax (expense) recovery effect of $183, $241 and $132 for the year ended June 30, 2018, 2017 and 2016, respectively Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, after Tax Unrealized net gain (loss) on marketable securities - net of tax effect of nil for the year ended June 30, 2018, 2017 and 2016, respectively Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Release of unrealized gain on marketable securities - net of tax effect of nil for the year ended June 30, 2018, 2017 and 2016, respectively Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Total other comprehensive income (loss) net, for the period Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Total comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive (income) loss attributable to non-controlling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Total comprehensive income attributable to OpenText Comprehensive Income (Loss), Net of Tax, Attributable to Parent Use of estimates Use of Estimates, Policy [Policy Text Block] Cash and cash equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Short-Term Investments Short-Term Investments [Policy Text Block] Short-Term Investments [Policy Text Block] Allowance for doubtful accounts Allowance For Doubtful Accounts, Policy [Policy Text Block] Allowance For Doubtful Accounts, Policy [Policy Text Block] Property and equipment Property, Plant and Equipment, Impairment [Policy Text Block] Capitalized Software Capitalization of Internal Costs, Policy [Policy Text Block] Acquired intangibles Intangible Assets, Finite-Lived, Policy [Policy Text Block] Impairment of long-lived assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Business combinations Business Combinations and Other Purchase of Business Transactions, Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Derivative financial instruments Derivatives, Policy [Policy Text Block] Asset retirement obligations Asset Retirement Obligations Policy Operating Leases [Policy Text Block] Asset Retirement Obligations Policy Operating Leases [Policy Text Block] Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Disclosure of accounting policy for revenue from contract with customer. Research and development costs Research, Development, and Computer Software, Policy [Policy Text Block] Income taxes Income Tax, Policy [Policy Text Block] Fair value of financial instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Foreign currency Foreign Currency Transactions and Translations Policy [Policy Text Block] Restructuring charges Costs Associated with Exit or Disposal Activities or Restructurings, Policy [Policy Text Block] Loss Contingencies Litigation [Policy Text Block] Litigation [Policy Text Block] Net income per share Earnings Per Share, Policy [Policy Text Block] Share-based payment Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Accounting for Pensions, post-retirement and post-employment benefits Pension and Other Postretirement Plans, Policy [Policy Text Block] Recent Accounting Pronouncements and ASUs adopted in Fiscal 2018 New Accounting Pronouncements, Policy [Policy Text Block] Daegis Inc. Daegis Inc. [Member] Daegis Inc. [Member] Purchase of business, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Stock Options Employee Stock Option [Member] Common shares available for issuance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Expiration period of options, minimum term Share-based Compensation Arrangement by Share-based Payment Award, Award Expire Period, Minimum Share-based Compensation Arrangement by Share-based Payment Award, Award Expire Period, Minimum Expiration period of options, maximum term Share-based Compensation Arrangement by Share-based Payment Award, Award Expire Period, Maximum Share-based Compensation Arrangement by Share-based Payment Award, Award Expire Period, Maximum Unrecognized compensation cost relating to unvested stock awards Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unvested stock awards compensation cost, weighted average recognition period Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Cash used to settle awards Employee Service Share-based Compensation, Cash Flow Effect, Cash Used to Settle Awards Capitalized amount of share-based compensation costs Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount Cash proceeds from exercise of options granted Proceeds from Stock Options Exercised Tax benefit realized from exercise of options Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Workforce Reduction Employee Severance [Member] Facility Costs Facility Closing [Member] Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Balance payable as at June 30, 2017 Restructuring Reserve Accruals and adjustments Restructuring Reserve, Accrual Adjustment Cash payments Payments for Restructuring Foreign exchange and other non-cash adjustments Restructuring Reserve, Foreign Currency Translation Gain (Loss) and Settled without Cash Restructuring Reserve, Foreign Currency Translation Gain (Loss) and Settled without Cash Balance payable as at June 30, 2018 Receivables [Abstract] ALLOWANCE FOR DOUBTFUL ACCOUNTS Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract] DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES Derivative Instruments and Hedging Activities Disclosure [Text Block] Cash paid during the period for interest Interest Paid, Net Cash received during the period for interest Interest Received, Net Interest Received, Net Cash paid during the period for income taxes Income Taxes Paid, Net Schedule of Long-Term Debt Schedule of Debt [Table Text Block] Long Term Incentive Plan Long Term Incentive Plan [Member] Long Term Incentive Plan [Member] Term of plan Stock issued (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Stock issued Stock Issued During Period, Value, Restricted Stock Award, Gross Compensation cost related to unvested awards not yet recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options Revenue From External Customers Attributed To Foreign Countries By Geographic Area Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block] Entity-Wide Disclosure On Geographic Areas, Long-Lived Assets In Individual Foreign Countries By Country Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block] Assets, Level 1 to Level 2 transfers Fair Value, Assets, Level 1 to Level 2 Transfers, Amount Liabilities, Level 1 to Level 2 transfers Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount Assets, Level 2 to Level 1 transfers Fair Value, Assets, Level 2 to Level 1 Transfers, Amount Liabilities, Level 2 to Level 1 transfers Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount Asset transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Liability transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3 Asset transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Liability transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3 Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Appraisal Proceedings Appraisal Proceedings [Member] Appraisal Proceedings [Member] Business Combination, Consideration Transferred [Abstract] Business Combination, Consideration Transferred [Abstract] Cash consideration Payments to Acquire Businesses, Gross Guidance shares already owned by OpenText through open market purchases (at fair value) Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value Preliminary purchase consideration Cash acquired from acquisition Cash Acquired from Acquisition Remeasurement gain Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain EARNINGS PER SHARE Earnings Per Share [Text Block] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Capitalized software development costs Capitalized Software [Member] Capitalized Software [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Useful life Property, Plant and Equipment, Useful Life Capitalized software development costs Capitalized Computer Software, Gross Additions related to capitalized software development costs Capitalized Computer Software, Additions Fiscal 2019 Restructuring Plan Fiscal 2019 Restructuring Plan [Member] Fiscal 2019 Restructuring Plan [Member] Expected restructuring costs Restructuring and Related Cost, Expected Cost Goodwill impairment Goodwill, Impairment Loss SUBSEQUENT EVENTS Subsequent Events [Text Block] Payments of dividends Payments of Dividends Preference shares issued (in shares) Preferred Stock, Shares Issued Common shares repurchased (in shares) Treasury Stock, Shares, Acquired Purchase of treasury stock Payments for Repurchase of Common Stock Issuance of treasury stock (in shares) Stock Issued During Period, Shares, Treasury Stock Reissued Contributions made by employer to plan Defined Benefit Plan, Plan Assets, Contributions by Employer Amount to be amortized from accumulated other comprehensive income (loss) over the next fiscal year Defined Benefit Plan, Expected Amortization, Next Fiscal Year Fair value of plan assets Defined Benefit Plan, Fair Value of Plan Assets Deposits and restricted cash Restricted Cash and Investments, Noncurrent Deferred implementation costs Other Deferred Costs, Net Investments Equity Method Investments Marketable securities Marketable Securities Long-term prepaid expenses and other long-term assets Prepaid Expense and Other Assets, Noncurrent Total other assets Other Assets, Noncurrent Schedule of Income before Income Tax, Domestic and Foreign Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Summary of Income Tax Contingencies Summary of Income Tax Contingencies [Table Text Block] Interest and Penalties Related to Liabilities for Income Tax Expense Schedule Of Interest And Penalties Related To Liabilities For Income Tax Expense [Table Text Block] Schedule of interest and penalties related to liabilities for income tax expense [Table Text Block] Interest Accrued and Penalties Accrued Related to Income Tax Expense Schedule Of Interest Accrued And Penalties Accrued Related To Income Tax Expense [Table Text Block] Schedule of interest accrued and penalties accrued related to income tax expense [Table Text Block] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Amortization of actuarial (gains) and losses Defined Benefit Plan, Amortization of Gain (Loss) Net pension expense Pension Cost (Reversal of Cost) Special Charges Special Charges [Member] Special Charges [Member] One-time ERP Implementation Project One-time ERP Implementation Project [Member] One-time ERP Implementation Project [Member] System Implementation Costs System Implementation Costs [Member] System Implementation Costs [Member] Miscellaneous Other Charges Miscellaneous Other Charges [Member] Miscellaneous Other Charges [Member] Pre-acquisition Sales and Use Tax Liabilities Pre-Acquisition Sales And Use Tax Liabilities [Member] Pre-Acquisition Sales And Use Tax Liabilities [Member] Pre-Acquisition Tax Liabilities being Settled, Released, or Statute Barred Pre-Acquisition Tax Liabilities Becoming Statute Barred [Member] Pre-Acquisition Tax Liabilities Becoming Statute Barred [Member] Commitment Fees Commitment Fees [Member] Commitment Fees [Member] Post-Acquisition Integration Costs Post-Acquisition Integration Costs [Member] Post-Acquisition Integration Costs [Member] Assets Disposed Assets Disposed [Member] Assets Disposed [Member] Interest on Certain Pre-Acquisition Liabilities Interest on Certain Pre-Acquisition Liabilities [Member] Interest on Certain Pre-Acquisition Liabilities [Member] Special charges recorded to date Restructuring and Related Cost, Cost Incurred to Date Accounting Standards Update 2016-16 Accounting Standards Update 2016-16 [Member] Decrease in assets Assets Decrease in liabilities Liabilities Decrease in retained earnings Fair Value of Derivative Instruments in the Condensed Consolidated Balance Sheets Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Effects of Derivative Instruments on Income and Other Comprehensive Income (OCI) Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block] ACCOUNTS PAYABLE AND ACCRUED LIABILITIES Accounts Payable and Accrued Liabilities Disclosure [Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Calculation of Acquired Intangibles by Asset Class Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block] Calculation of Estimated Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Deferred Costs [Abstract] DEFERRED CHARGES AND CREDITS Disclosure of Deferred Charges [Text Block] Disclosure of Deferred Charges [Text Block] Senior Notes Senior Notes [Member] Senior Notes 2026 Senior Notes 2026 [Member] Senior Notes 2026 [Member] Senior Notes 2023 Senior Notes 2023 [Member] Senior Notes 2023 [Member] Debt instrument stated interest rate Debt Instrument, Interest Rate, Stated Percentage Debt premium issue price percentage Debt Instrument, Issuance Price, Percentage of Face Value Debt Instrument, Issuance Price, Percentage of Face Value ACQUIRED INTANGIBLE ASSETS Intangible Assets Disclosure [Text Block] Schedule of Defined Benefit Plan and Long-Term Employee Benefit Obligations Schedule of Defined Benefit Plan and Long Term Employee Benefit Obligation [Table Text Block] Schedule of Defined Benefit Plan and Long Term Employee Benefit Obligation [Table Text Block] Schedule of the Change in the Benefit Obligation of Defined Benefit Plan Schedule of Changes in Projected Benefit Obligations [Table Text Block] Components of Net Pension Expense for Pension Plan Schedule of Net Benefit Costs [Table Text Block] Schedule of Weighted-Average Key Assumptions Used for CDT Pension Plan Schedule of Assumptions Used [Table Text Block] Anticipated Pension Payments Under Pension Plan Schedule of Expected Benefit Payments [Table Text Block] Exercise Price Range [Axis] Exercise Price Range [Axis] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain] Stock Options Exercise Price Range One Stock Options Exercise Price Range One [Member] Stock Options Exercise Price Range One [Member] Stock Options Exercise Price Range Two Stock Options Exercise Price Range Two [Member] Stock Options Exercise Price Range Two [Member] Stock Options Exercise Price Range Three Stock Options Exercise Price Range Three [Member] Stock Options Exercise Price Range Three [Member] Stock Options Exercise Price Range Four Stock Options Exercise Price Range Four [Member] Stock Options Exercise Price Range Four [Member] Stock Options Exercise Price Range Five Stock Options Exercise Price Range Five [Member] Stock Options Exercise Price Range Five [Member] Stock Options Exercise Price Range Six Stock Options Exercise Price Range Six [Member] Stock Options Exercise Price Range Six [Member] Stock Options Exercise Price Range Seven Stock Options Exercise Price Range Seven [Member] Stock Options Exercise Price Range Seven [Member] Stock Options Exercise Price Range Eight Stock Options Exercise Price Range Eight [Member] Stock Options Exercise Price Range Eight [Member] Stock Options Exercise Price Range Nine Stock Options Exercise Price Range Nine [Member] Stock Options Exercise Price Range Nine [Member] Stock Options Exercise Price Range Ten Stock Options Exercise Price Range Ten [Member] Stock Options Exercise Price Range Ten [Member] Stock Options Exercise Price Range Eleven Stock Options Exercise Price Range Eleven [Member] Stock Options Exercise Price Range Eleven [Member] Range of Exercise Prices Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Abstract] Minimum (in dollars per share) Maximum (in dollars per share) Options Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Abstract] Number of options Outstanding as of June 30, 2018 Weighted Average Remaining Contractual Life (years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Options Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable [Abstract] Number of options Exercisable as of June 30, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Related Party Transaction, Due from (to) Related Party [Abstract] RELATED PARTY TRANSACTIONS Related Party Transactions Disclosure [Text Block] Total debt Premium on Senior Notes 2026 Debt Instrument, Unamortized Premium Debt issuance costs Total amount outstanding Long-term Debt Less: Long-term Debt, Current and Noncurrent [Abstract] Current portion of long-term debt Loans Payable to Bank, Current Non-current portion of long-term debt Loans Payable to Bank, Noncurrent Changes in Carrying Amount of Allowance For Doubtful Accounts Schedule of Accounts Receivable, Allowance for Doubtful Accounts [Table Text Block] Schedule of Accounts Receivable, Allowance for Doubtful Accounts [Table Text Block] Statement of Cash Flows [Abstract] Statement [Table] Statement [Table] HP Inc. CCM Business Acquisitions completed prior to Fiscal 2017 Acquisitions Prior To Current Year [Member] Acquisitions Prior To Current Year [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Shares Common Stock [Member] Treasury Stock Treasury Stock [Member] Statement [Line Items] Statement [Line Items] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization of intangible assets Depreciation, Depletion and Amortization Share-based compensation expense Share-based Compensation Excess tax (benefits) expense on share-based compensation expense Excess Tax Benefit from Share-based Compensation, Operating Activities Pension expense Amortization of debt issuance costs Amortization of Debt Issuance Costs Amortization of deferred charges and credits Amortization of Other Deferred Charges Loss on sale and write down of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Release of unrealized gain on marketable securities to income Marketable Securities, Gain (Loss), Excluding Other than Temporary Impairments Deferred taxes Share in net (income) loss of equity investees Income (Loss) from Equity Method Investments Other non-cash charges Other Noncash Expense Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Receivables Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Income taxes and deferred charges and credits Increase (Decrease) in Income Taxes Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Deferred revenue Increase (Decrease) In Contract With Customer, Liability Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable. Other assets Increase (Decrease) in Other Operating Assets Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Additions of property and equipment Payments to Acquire Productive Assets Proceeds from maturity of short-term investments Proceeds from Sale, Maturity and Collection of Investments Purchase of business, net of cash acquired Other investing activities Payments to Acquire Marketable Securities Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Excess tax benefits (expense) on share-based compensation expense Excess Tax Benefit from Share-based Compensation, Financing Activities Proceeds from long-term debt and Revolver Proceeds from Issuance of Long-term Debt Proceeds from issuance of Common Shares from exercise of stock options and ESPP Proceeds from Issuance of Common Stock Proceeds from issuance of Common Shares under the public Equity Offering Proceeds from Issuance or Sale of Equity Repayment of long-term debt and Revolver Repayments of Long-term Debt Debt issuance costs Equity issuance costs Payments of Stock Issuance Costs Common Shares repurchased Purchase of non-controlling interest Payments to Noncontrolling Interests Payments of dividends to shareholders Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Foreign exchange gain (loss) on cash held in foreign currencies Effect of Exchange Rate on Cash and Cash Equivalents Increase (decrease) in cash and cash equivalents during the period Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of the period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of the period Expected statutory rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Expected provision for income taxes Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Effect of foreign tax rate differences Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Amortization of deferred charges Income Tax Reconciliation Amortization of Deferred Charges Income Tax Reconciliation Amortization of Deferred Charges Effect of permanent differences Income Tax Reconciliation Effect of Permanent Difference Income Tax Reconciliation Effect of Permanent Difference Effect of changes in unrecognized tax benefits Income Tax Reconciliation Tax Reserve Income Tax Reconciliation Tax Reserve Effect of withholding taxes Income Tax Reconciliation Withholding Tax Income Tax Reconciliation Withholding Tax Difference in tax filings from provision Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount Other Items Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Impact of internal reorganization of subsidiaries Total revenues Revenues Percentage for allowance maintained on bad-debts Percentage for Allowance Maintained on Bad-Debts Percentage for Allowance Maintained on Bad-Debts Allowance for Doubtful Accounts Receivable [Roll Forward] Allowance for Doubtful Accounts Receivable [Roll Forward] Balance as of beginning of the period Allowance for Doubtful Accounts Receivable, Current Bad debt expense Provision for Doubtful Accounts Write-off /adjustments Doubtful Accounts Adjustment For Write-down Doubtful Accounts, Adjustment for Write-down Balance as of end of the period Unbilled receivables Unbilled Contracts Receivable Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets, Net [Abstract] Finite-Lived Intangible Assets, Net [Abstract] Cost Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Total Finite-Lived Intangible Assets, Net Intangible assets fully amortized during the period Finite-Lived Intangible Assets, Fully Amortized During the Period Finite-Lived Intangible Assets, Fully Amortized During the Period Weighted-average amortization period (in years) for acquired intangible assets Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Benefit obligation—beginning of period Defined Benefit Plan, Benefit Obligation Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Actuarial (gain) loss Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Foreign exchange (gain) loss Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss) Benefit obligation—end of period Less: Current portion Liability, Defined Benefit Pension Plan, Current Non-current portion of benefit obligation Liability, Defined Benefit Pension Plan, Noncurrent Statement of Stockholders' Equity [Abstract] Common Shares and Additional Paid in Capital Common Stock Including Additional Paid in Capital [Member] Retained Earnings Retained Earnings [Member] Accumulated Other Comprehensive Income AOCI Attributable to Parent [Member] Non-Controlling Interests Noncontrolling Interest [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Balance (in shares) Shares, Issued Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Issuance of Common Shares Stock Issued or Granted During Period, Share-based Compensation [Abstract] Under employee stock option plans (in shares) Under employee stock option plans Stock Issued During Period, Value, Stock Options Exercised Under employee stock purchase plans (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Under employee stock purchase plans Stock Issued During Period, Value, Employee Stock Purchase Plan Under the public Equity Offering (in shares) Stock Issued During Period, Shares, New Issues Under the public Equity Offering Stock Issued During Period, Value, New Issues Income tax effect related to public Equity Offering Income Tax Effects Allocated Directly to Equity, Equity Transactions Equity issuance costs Equity Issuance Costs Equity Issuance Costs Share-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Income tax effect related to share-based compensation Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Purchase of treasury stock (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Shares Purchased for Award Purchase of treasury stock Treasury Stock, Value, Acquired, Cost Method Issuance of treasury stock Stock Issued During Period, Value, Treasury Stock Reissued Commons Shares repurchased (in shares) Stock Repurchased and Retired During Period, Shares Common Shares repurchased Stock Repurchased and Retired During Period, Value Dividends Dividends Other comprehensive income (loss) - net Non-controlling interest Non-controlling Interest Non-controlling Interest Net income for the year Balance (in shares) Balance Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Ownership percentage Equity Method Investment, Ownership Percentage Income (loss) from equity method investments Summary of Changes In Carrying Amount of Goodwill Schedule of Goodwill [Table Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Accounts Payable and Accrued Liabilities Accounts Payable and Accrued Liabilities [Member] Prepaid expenses and other current assets Prepaid Expenses and Other Current Assets [Member] Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Cash Flow Hedging Cash Flow Hedging [Member] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Designated As Hedging Instrument Designated as Hedging Instrument [Member] Derivative Instrument Risk [Axis] Derivative Instrument [Axis] Derivative Contract Type [Domain] Derivative Contract [Domain] Foreign currency forward contracts Foreign Exchange Forward [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Contract maturity Derivative, Term of Contract Notional amount of forward contracts held to sell U.S. dollars in exchange for Canadian dollars Derivative, Notional Amount Fair Value Asset (Liability) Derivative Assets (Liabilities), at Fair Value, Net Income Statement [Abstract] Revenues: Revenues [Abstract] License Licenses Revenue Cloud services and subscriptions Cloud Services Revenue Cloud Services Revenue Customer support Maintenance Revenue Professional service and other Professional Service and other revenue Revenue from providing technology services. The services may include training, installation, engineering or consulting. Consulting services often include implementation support, software design or development, or the customization or modification of the licensed software. And also, aggregate revenue during the period from the sale of goods in the normal course of business, before deducting returns, allowances and discounts. Total revenues Cost of revenues: Cost of Revenue [Abstract] License License Costs Cloud services and subscriptions Cloud Services Cost Of Revenue Cloud Services Cost Of Revenue Customer support Cost of Services, Maintenance Costs Professional service and other Professional Service and other cost of revenue Costs incurred in providing technology services. The services may include training, installation, engineering or consulting. Consulting services often include implementation support, software design or development, or the customization or modification of the licensed software. Also includes service costs incurred and are directly related to the goods produced and sold during the reporting period. Amortization of acquired technology-based intangible assets (note 6) Amortization of Intangible Assets Total cost of revenues Cost of Revenue Gross profit Gross Profit Operating expenses: Operating Expenses [Abstract] Research and development Research and Development Expense (Excluding Acquired in Process Cost) Sales and marketing Selling and Marketing Expense General and administrative General and Administrative Expense Depreciation Depreciation, Nonproduction Amortization of acquired customer-based intangible assets (note 6) Amortization Of Other Intangible Assets Amortization of other intangible assets (for example customer relationships and trade names) incurred by an entity during the reporting period. Special charges (recoveries) (note 17) Total operating expenses Operating Expenses Income from operations Operating Income (Loss) Other income (expense), net Other Nonoperating Income (Expense) Interest and other related expense, net Interest Income (Expense), Net Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for (recovery of) income taxes (note 14) Net income for the period Net (income) loss attributable to non-controlling interests Net Income (Loss) Attributable to Noncontrolling Interest Net income attributable to OpenText Earnings per share—basic attributable to OpenText (note 21) (in dollars per share) Earnings per share—diluted attributable to OpenText (note 21) (in dollars per share) Weighted average number of Common Shares outstanding—basic (in '000's) (in shares) Weighted average number of Common Shares outstanding—diluted (in '000's) (in shares) Dividends declared per Common Share (in dollars per share) OTHER ASSETS Investments and Other Noncurrent Assets [Text Block] GUARANTEES AND CONTINGENCIES Commitments Contingencies and Guarantees [Text Block] Impairment of long-lived assets Impairment of Long-Lived Assets to be Disposed of Statement of Financial Position [Abstract] ASSETS Assets [Abstract] Cash and cash equivalents Accounts receivable trade, net of allowance for doubtful accounts of $9,741 as of June 30, 2018 and $6,319 as of June 30, 2017 (note 3) Accounts Receivable, Net, Current Income taxes recoverable (note 14) Income Taxes Receivable, Current Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Property and equipment (note 4) Property, Plant and Equipment, Net Goodwill (note 5) Acquired intangible assets (note 6) Intangible Assets, Net (Excluding Goodwill) Deferred tax assets (note 14) Deferred Income Tax Assets, Net Other assets (note 7) Deferred charges (note 8) Deferred Costs, Noncurrent Long-term income taxes recoverable (note 14) Income Taxes Receivable, Noncurrent Total assets LIABILITIES AND SHAREHOLDERS’ EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable and accrued liabilities (note 9) Current portion of long-term debt (note 10) Long-term Debt, Current Maturities Deferred revenues Contract with Customer, Liability, Current Income taxes payable (note 14) Accrued Income Taxes, Current Total current liabilities Liabilities, Current Long-term liabilities: Liabilities, Noncurrent [Abstract] Accrued liabilities (note 9) Deferred credits (note 8) Other Deferred Credits, Noncurrent Pension liability (note 11) Long-term debt (note 10) Deferred revenues Contract with Customer, Liability, Noncurrent Long-term income taxes payable (note 14) Liability for Uncertainty in Income Taxes, Noncurrent Deferred tax liabilities (note 14) Deferred Income Tax Liabilities, Net Total long-term liabilities Liabilities, Noncurrent Shareholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Share capital and additional paid-in capital (note 12) 267,651,084 and 264,059,567 Common Shares issued and outstanding at June 30, 2018 and June 30, 2017, respectively; authorized Common Shares: unlimited Common Stock, Value, Outstanding Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Retained earnings Treasury stock, at cost (690,336 shares at June 30, 2018 and 1,101,612 at June 30, 2017, respectively) Treasury Stock, Value Total OpenText shareholders' equity Stockholders' Equity Attributable to Parent Non-controlling interests Stockholders' Equity Attributable to Noncontrolling Interest Total shareholders’ equity Total liabilities and shareholders’ equity Liabilities and Equity Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table] Derivative Instruments, Gain (Loss) [Table] Operating Expenses Operating Expense [Member] Amount of Gain or (Loss) Recognized in OCI on Derivatives (Effective Portion) Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net Amount of Gain or (Loss) Recognized in Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing) Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net SHARE CAPITAL, OPTION PLANS AND SHARE-BASED PAYMENTS Shareholders' Equity and Share-based Payments [Text Block] Number of reportable segments Number of Reportable Segments Accounts receivable trade, allowance for doubtful accounts Common shares issued (in shares) Common Stock, Shares, Issued Common shares outstanding (in shares) Common Stock, Shares, Outstanding Treasury stock (in shares) Treasury Stock, Shares Components of Property and Equipment by Type FAIR VALUE MEASUREMENT Fair Value Disclosures [Text Block] Weighted-average fair value of options granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted-average assumptions used: Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate Risk–free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Expected life (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Forfeiture rate (based on historical rates) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Forfeiture Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Forfeiture Rate Average exercised share price (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Average Exercise Price Derived service period (in years) Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period SUPPLEMENTAL CASH FLOW DISCLOSURES Cash Flow, Supplemental Disclosures [Text Block] GOODWILL Goodwill Disclosure [Text Block] Cash acquired from acquisition Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Unrecognized tax benefits as of Beginning of the Period Unrecognized Tax Benefits Increases on account of current year positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Increases on account of prior year positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Decreases due to settlements with tax authorities Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Decreases due to lapses of statutes of limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Unrecognized tax benefits as of End of the Period Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Measurements, Recurring [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Significant other observable inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Financial Assets: Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Alternative [Abstract] Derivative financial instrument asset (note 16) Derivative Asset Financial Assets Assets, Fair Value Disclosure, Recurring Financial Liabilities: Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis, Alternative [Abstract] Derivative financial instrument liability (note 16) Derivative Liability Financial Liabilities Liabilities, Fair Value Disclosure, Recurring Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding at beginning of period (in shares) Granted (in shares) Exercised (in shares) Forfeited or expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Outstanding at end of period (in shares) Exercisable ending balance (in shares) Weighted- Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Outstanding at beginning of period (in dollars per share) Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Forfeited or expired (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Outstanding at end of period (in dollars per share) Exercisable at end of period (in dollars per share) Weighted- Average Remaining Contractual Term (years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Additional Disclosures [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Additional Disclosures [Abstract] Outstanding (in years) Exercisable (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate Intrinsic Value ($’000s) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value, Additional Disclosures [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value, Additional Disclosures [Abstract] Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Schedule of Deferred Charges and Credits [Table] Schedule of Deferred Charges and Credits [Table] Schedule of Deferred Charges and Credits [Table] Schedule of Deferred Charges and Credits [Line Items] Schedule of Deferred Charges and Credits [Line Items] [Line Items] for Schedule of Deferred Charges and Credits [Table] Deferred charges and credits amortization, period Deferred Charges Amortization Period Deferred Charges Amortization Period Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Director, Stephen Sadler Director [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Consultancy fees for business acquisition-related activities Professional Fees PENSION PLANS AND OTHER POST RETIREMENT BENEFITS Pension and Other Postretirement Benefits Disclosure [Text Block] Furniture and fixtures Furniture and Fixtures [Member] Office equipment Office Equipment [Member] Computer hardware Computer Hardware [Member] Computer Hardware [Member] Computer software Computer Software [Member] Computer Software [Member] Leasehold improvements Leasehold Improvements [Member] Building Building [Member] Impairment charges for long-lived assets Tangible Asset Impairment Charges Schedule of Share-based Compensation, Stock Options, Outstanding Under Various Plans Schedule of Share-based Compensation, Stock Options, Outstanding Under Various Plans [Table Text Block] Schedule of Share-based Compensation, Stock Options, Outstanding Under Various Plans [Table Text Block] Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block] Summary of Share-based Compensation Costs Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] Summary of Option Activity Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Weighted-Average Fair Value of Options and Weighted-Average Assumptions Used Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] 2019 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five 2024 and beyond Finite-Lived Intangible Assets, Amortization Expense, after Year Five Schedule of Goodwill [Table] Schedule of Goodwill [Table] Goodwill [Line Items] Goodwill [Line Items] Goodwill [Roll Forward] Goodwill [Roll Forward] Balance as of June 30, 2017 Acquisition (note 18) Goodwill, Acquired During Period Adjustments relating to acquisitions prior to current fiscal year that had open measurement periods (note 18) Goodwill, Purchase Accounting Adjustments Adjustments on account of foreign exchange Goodwill, Foreign Currency Translation Gain (Loss) Balance as of June 30, 2018 Computer software Land and buildings Cost Property, Plant and Equipment, Gross Accumulated Depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Net Noncontrolling Interest [Table] Noncontrolling Interest [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] OT South Africa Open Text South Africa Proprietary Ltd [Member] Open Text South Africa Proprietary Ltd GXS Korea GXS Korea [Member] GXS Korea [Member] GXS Singapore EC1 Pte. Ltd [Member] EC1 Pte. Ltd [Member] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Ownership percentage by Open Text Noncontrolling Interest, Ownership Percentage by Parent Interest expense accrued Unrecognized Tax Benefits, Interest on Income Taxes Accrued Penalties accrued Unrecognized Tax Benefits, Income Tax Penalties Accrued Unrealized gain (loss) on cash flow hedges, tax (recovery) expense Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax (Gain) loss reclassified into net income, tax (expense) recovery Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax Actuarial gain (loss), tax (recovery) expense Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax Amortization of actuarial (gain) loss into net income, tax recovery (expense) Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, Tax Unrealized net gain (loss) on marketable securities, tax effect Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Release of unrealized gain on marketable securities, tax effect Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Present value of asset retirement obligation Asset Retirement Obligation Present Value The present value of a liability for an asset retirement obligation associated with the disposal or retirement of a tangible long-lived asset that results from acquisition, construction or development, or the normal operations of a long-lived asset including obligations from operating leases. Undiscounted value of asset retirement obligation Asset Retirement Obligation Undiscounted Value Asset Retirement Obligation Undiscounted Value Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Deferred Stock Units (DSUs) Deferred Stock Units [Member] Deferred Stock Units [Member] Employee Share Purchase Plan (ESPP) Employee Stock [Member] Units granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Awards purchase price discount Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price Discount Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price Discount Common shares eligible for issuance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Shares Eligible for Issuance Share-based Compensation Arrangement by Share-based Payment Award, Shares Eligible for Issuance Cash received from employee stock purchase plan Cash Received From Employee Stock Purchase Plan Cash collected to be used to purchase Common Stock in future periods Contract assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Contract Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Contract Assets Shares outstanding at acquisition (in shares) Loss Contingency, Issued and Outstanding Shares at Acquisition Loss Contingency, Issued and Outstanding Shares at Acquisition Percent of shares outstanding Loss Contingency, Percent of Shares Outstanding Loss Contingency, Percent of Shares Outstanding Share price (in dollars per share) Business Acquisition, Share Price Performance Stock Units (PSUs) Performance Stock Units [Member] Performance Stock Units [Member] Deferred Share Units (directors) Employee Share Purchase Plan Other plans Other Plans [Member] Other Plans [Member] Share-based compensation expense Allocated Share-based Compensation Expense