Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Trading Arrangement: Trading Arrangement [Axis] Maximum Maximum [Member] Public, Project and Infrastructure Finance (PPIF) Public Project And Infrastructure Finance [Member] Consists of revenue from rating and monitoring U.S. public debt issued by state and local governments, hospitals, higher education institutions and other U.S. tax-exempt entities. Additionally, includes revenue from rating and monitoring sovereign nations, central government agencies and sovereign-related companies as well as non-U.S. regional and local governments and other related public sector entities including mass transportation, health care, water systems, social housing, higher education and charity trusts. Also includes revenue from rating and monitoring both public and private infrastructure and project finance issuers both in the U.S. and internationally, including electric, gas and water utility companies. Title of 12(b) Security Title of 12(b) Security Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Adjustment to Compensation, Amount Adjustment to Compensation Amount Contracts to sell USD for CAD Foreign Currency Forward Contracts to Sell US Dollars for Canadian Dollars [Member] A forward currency contract to sell USD and buy CAD. Financial Instrument [Axis] Financial Instrument [Axis] Segment Reporting [Abstract] Segment Reporting [Abstract] Restructuring Plan [Axis] Restructuring Plan [Axis] Salaries and benefits Employee-related Liabilities, Current Contracts to sell USD for EUR Foreign Currency Forward Contracts To Sell US Dollars For Euros [Member] A forward currency contract to sell USD and buy Euros. 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169,721,288 and 165,359,285 shares of common stock at June 30, 2026 and December 31, 2025, respectively Treasury Stock, Common, Value Data and Information (D&I) Data and Information [Member] Data and Information Income tax, increase (decrease) percentage Income Tax, Increase (Decrease) Percentage Income Tax, Increase (Decrease) Percentage Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Fixed Rate [Domain] Fixed Rate [Domain] Fixed Rate Fair value of shares vested Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Accumulated other comprehensive loss Cumulative Gains (Losses), net of tax Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Currency Swap One Currency Swap One [Member] Currency Swap One Consolidation Items [Domain] Consolidation Items [Domain] Schedule of Net Investment Hedges, Notional Amount That Will Be Settled At Expiry Schedule of Net Investment Hedges, Notional Amount That Will Be Settled At Expiry [Table Text Block] Schedule of Net Investment Hedges, Notional Amount That Will Be Settled At Expiry Current portion of operating lease liabilities Lease liabilities - current Operating Lease, Liability, Current Cash and Cash Equivalents [Line Items] Cash and Cash Equivalents [Line Items] RECONCILIATION OF WEIGHTED AVERAGE SHARES OUTSTANDING Earnings Per Share [Text Block] Earnings per share attributable to Moody's common shareholders Earnings Per Share [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Contracts to sell USD for SGD Foreign Currency Forward Contracts to Sell US Dollars for Singapore Dollars [Member] A forward currency contract to sell USD and buy Singapore dollars. 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MA Moodys Analytics [Member] Member related to operating segment Moodys Analytics. Personnel Costs Including Severance and Other Related Costs Personnel Costs Including Severance and Other Related Costs [Member] Personnel Costs Including Severance and Other Related Costs Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Disposal Group Name [Domain] Disposal Group Name [Domain] Dividends Dividends Share-based Payment Arrangement, Option, Exercise Price Range [Table] Share-Based Payment Arrangement, Option, Exercise Price Range [Table] Entities [Table] Entities [Table] Operating Lease, Lease Not yet Commenced Operating Lease, Lease Not yet Commenced [Member] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Percentage of leased floors accessed Percentage Of Floors With Lease Commencement Percentage Of Floors With Lease Commencement Other Other Intangible Assets [Member] Cash paid for amounts included in the measurement of operating lease liabilities Operating Lease, Payments Award Timing Predetermined Award Timing Predetermined [Flag] Aggregate intrinsic value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Stock-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Level 1 Fair Value, Inputs, Level 1 [Member] Derivative instruments designated as accounting hedges Derivative Asset, Noncurrent Effective tax rate (percent) Effective Income Tax Rate Reconciliation, Percent Dilutive effect of shares issuable under stock-based compensation plans (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Fair value changes on hedged debt Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge Lease obligations Increase (Decrease) in Operating Lease Liability Net actuarial gains (losses) - Net of Tax Net actuarial gains (losses), net of tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax Preferred stock, par value (in usd per share) Preferred Stock, Par or Stated Value Per Share Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Scenario [Domain] Scenario [Domain] Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Lessee, operating lease, renewal term (years) Lessee, Operating Lease, Renewal Term Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Other Comprehensive Income (Loss): Foreign Currency Translation [Abstract] Fair value changes on interest rate swaps Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments Dividends Payments of Ordinary Dividends, Common Stock Expiration Date Trading Arrangement Expiration Date 2030 Long-Term Debt, Maturity, Year Four Hedging Relationship [Axis] Hedging Relationship [Axis] CMBS Commercial Mortgage-backed Securities Product [Member] Consists of revenue relating to commercial real estate finance. Goodwill, other increase (decrease) Goodwill, Other Increase (Decrease) Americas Americas [Member] Total shareholders' equity Beginning Balance Ending Balance Equity, Including Portion Attributable to Noncontrolling Interest Floating Interest Rate Description of Interest Rate Fair Value Hedge Activities Corporate Finance (CFG) Corporate Finance [Member] Consists of revenue relating to the rating and monitoring of debt issued by commercial and industrial corporations. Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Derivative [Table] Derivative [Table] 2032 Net Investment Hedging Settlement Year Six [Member] Net Investment Hedging Settlement Year Six Unamortized (Discount) Premium Debt Instrument, Unamortized Discount (Premium), Net Cash flows from investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Unrecognized compensation expense Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Segments [Domain] Segments [Domain] Interest Rate Swap Interest rate swaps designated as fair value hedges Interest Rate Swap [Member] Expense on UTPs and other tax related liabilities Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense INDEBTEDNESS Debt Disclosure [Text Block] Contracts to sell USD for AUD Foreign Currency Forward Contracts To Sell Australian Dollars for US Dollars [Member] Foreign Currency Forward Contracts To Sell Australian Dollars for US Dollars Scenario [Axis] Scenario [Axis] Disposal Group Classification [Domain] Disposal Group Classification [Domain] Restructuring Expenses Included in Consolidated Statements of Operations Restructuring and Related Costs [Table Text Block] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Foreign exchange forwards on certain assets and liabilities Foreign Currency Contract, Asset, Fair Value Disclosure Total expenses Costs and Expenses Notes payable, interest rate Debt Instrument, Interest Rate, Stated Percentage Total Moody's shareholders' equity Equity, Attributable to Parent Disposal Group, Disposed of by Sale, Not Discontinued Operations Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] Pension and other retirement employee benefits Assets for Plan Benefits, Defined Benefit Plan ASSETS Assets [Abstract] Other Other Investments Performance Based Restricted Stock Performance Based Restricted Stock [Member] Non-market performance based restricted stock. Financial Institutions (FIG) Financial Institutions [Member] Revenue relating to the rating and monitoring of banks, securities firms, insurance providers as well as real estate and non-bank finance companies. Also encompasses ratings of mutual fund portfolios, pooled investment vehicles and alternative investments. Insider Trading Policies and Procedures [Line Items] Accounts receivable, allowances Accounts Receivable, Allowance for Credit Loss, Current Schedule of Operating Leases Information Other Information Related to Operating Leases [Table Text Block] Other Information Related to Operating Leases [Table Text Block] Deferred income taxes Deferred Income Tax Expense (Benefit) 2022 Senior Notes due 2052 Two Thousand and Twenty Two Senior Notes Due Two Thousand and Fifty Two [Member] Two Thousand and Twenty Two Senior Notes Due Two Thousand and Fifty Two Interest expense, net Interest expense, net Interest Income (Expense), Nonoperating Number of operating segments Number of Operating Segments Anti-dilutive options to purchase common shares and restricted stock as well as contingently issuable restricted stock which are excluded from the table above (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Capitalized costs to obtain sales contracts Capitalized Contract Cost, Net, Noncurrent Activity in Goodwill Goodwill [Table Text Block] Beginning balance, goodwill gross Ending balance, goodwill gross Goodwill, Gross Entity Central Index Key Entity Central Index Key Database Database Rights [Member] Accumulated depreciation, property and equipment Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization Capital surplus Additional Paid in Capital, Common Stock Equity [Abstract] Equity [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Cost incurred and adjustments Restructuring and Related Cost, Incurred Cost 2026 (After June 30,) Long-Term Debt, Maturity, Remainder of Fiscal Year Other comprehensive income (loss) before reclassifications Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Designated as Hedging Instrument Designated as Hedging Instrument [Member] MIS Moodys Investors Service [Member] Member related to operating segment Moodys Investors Service. Weighted Average Assumptions used in Determining Fair Value for Options Granted Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Company's Reportable Segment Revenues Disaggregated by Segment and Geographic Region Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Table Text Block] Fixed Pay Weighted Average Interest Rate Fixed Pay Weighted Average Interest Rate [Member] 1.51% fixed pay weighted average interest rate. Variable Rate [Domain] Variable Rate [Domain] Restricted Stock Restricted Stock [Member] Accumulated Other Comprehensive Loss Total AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] Weighted average period to recognize expense Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Statement [Line Items] Statement [Line Items] Total assets Assets 2028 Net Investment Hedging Settlement Year Two [Member] Net Investment Hedging Settlement Year Two Operating Segments Operating Segments [Member] Employee stock options, weighted average grant date fair value (in usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Investments measured using the measurement alternative Equity Securities without Readily Determinable Fair Value, Amount STOCK-BASED COMPENSATION Share-Based Payment Arrangement [Text Block] Non-compensation expense Non-Compensation Expense Non-Compensation Expense PEO PEO [Member] 2028 Long-Term Debt, Maturity, Year Two RMBS Residential Mortgage-backed Securities Product [Member] Consists of revenue relating to residential mortgage-backed securities product. Repurchase of shares related to stock-based compensation and excise tax payments on share repurchases Payment, Tax Withholding, Share Based Payment Arrangement and Excise Tax Payments On Share Repurchases Payment, Tax Withholding, Share Based Payment Arrangement and Excise Tax Payments On Share Repurchases Other liabilities Total other liabilities Other Liabilities, Noncurrent Goodwill Beginning balance, goodwill net Ending balance, goodwill net Goodwill Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Retained Earnings Retained Earnings [Member] Operating lease liabilities Lease liabilities - noncurrent Operating Lease, Liability, Noncurrent Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Foreign Currency Translation Adjustments Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Diluted (in usd per share) Earnings Per Share, Diluted Debt instrument, covenant compliance Debt Instrument, Covenant Compliance Other current assets Increase (Decrease) in Prepaid Expense and Other Assets Amortization expense Intangible Asset, Finite-Lived, Amortization Expense Intangible Asset, Finite-Lived [Line Items] Intangible Asset, Finite-Lived [Line Items] Currency Received Currency Received [Member] Currency received. MAKS indemnification provisions Disposal Group, Including Discontinued Operation, Indemnification Provision Liability Indemnification liability recorded pursuant to the divestiture of MAKS Revenue Revenue recognized Revenue from Contract with Customer, Excluding Assessed Tax Money market funds/mutual funds Mutual Funds and Money Market Funds [Member] Mutual Funds and Money Market Funds Series Common Stock Series Common Stock [Member] Series of common stock representing ownership interest in a corporation. Assets held-for-sale Disposal Group, Including Discontinued Operation, Assets, Current Changes to the Restructuring Liability Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Assets: Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Amortization of actuarial gains and prior service credits included in net income Amortization of actuarial gains and prior service credits included in net income Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Subsegments [Domain] Subsegments [Domain] Share repurchase program, excise tax Share Repurchase Program, Excise Tax Principal Payments Due on Long-Term Borrowings Schedule of Maturities of Long-Term Debt [Table Text Block] Insurance Insurance [Member] Consists of revenue relating to insurance. Net interest settlements and accruals on interest rate swaps Derivative, Gain (Loss) on Derivative, Net Operating income Operating Income (Loss) Revenue, remaining performance obligation, amount Revenue, Remaining Performance Obligation, Amount Cash Flow Hedges: Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax [Abstract] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Common stock, shares issued (in shares) Common stock, shares issued beginning balance (in shares) Common stock, shares issued ending balance (in shares) Common Stock, Shares, Issued DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION Business Description and Basis of Presentation [Text Block] Entity Information [Line Items] Entity Information [Line Items] Income tax examination, description Income Tax Examination, Description COMPREHENSIVE INCOME AND ACCUMULATED OTHER COMPREHENSIVE LOSS Comprehensive Income (Loss) Note [Text Block] Accounts receivable Increase (Decrease) in Accounts Receivable Product and Service [Domain] Product and Service [Domain] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Restructuring liability Restructuring Reserve, Current Long-term debt Long-Term Debt [Member] Deferred tax liabilities, net Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] 2029 Lessee, Operating Lease, Liability, to be Paid, Year Three Termination Date Trading Arrangement Termination Date Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Other accounts Other product lines [Member] Consists of revenue relating to other product lines. Currency translation adjustment, net of net investment hedge activity, tax expense (benefit) Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax Other liabilities: Other Liabilities [Abstract] Fair Value as of Grant Date Award Grant Date Fair Value Schedule of Goodwill [Table] Goodwill [Table] Foreign currency translation adjustments - Tax Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Before Reclassification, Tax Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Before Reclassification, Tax Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Arrangement Duration Trading Arrangement Duration 3.75% 2022 Senior Notes, due 2052 3.75% 2022 Senior Notes, due 2052 [Member] 3.75% 2022 Senior Notes, due 2052 Capitalized costs to obtain and fulfill sales contracts Capitalized Contract Cost, Net, Current Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions and Methodology [Abstract] Unrecognized tax benefits, period increase (decrease), net of federal tax benefits Unrecognized Tax Benefits, Period Increase (Decrease), Net of Federal Tax Benefits Unrecognized Tax Benefits, Period Increase (Decrease), Net of Federal Tax Benefits Fixed Received Weighted Average Interest Rate Fixed Received Weighted Average Interest Rate [Member] 4.13% fixed received weighted average interest rate. Charges related to asset abandonment Charges Related To Asset Abandonment Charges related to the Company's decision to outsource the production of certain sustainability content utilized in our product offerings, including both charges related to severance and accelerated amortization Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Acquired intangible assets, gross Intangible Asset, Finite-Lived, before Accumulated Amortization 3.25% 2020 Senior Notes, due 2050 3.25% 2020 Senior Notes, due 2050 [Member] 3.25% 2020 Senior Notes, due 2050 Income from investments in non-consolidated affiliates Income (Loss) from Equity Method Investments Other assets: Other Assets [Abstract] Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Award vesting period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Goodwill [Roll Forward] Goodwill [Roll Forward] 2.75% 2021 Senior Notes, due 2041 2.75% 2021 Senior Notes, due 2041 [Member] 2.75% 2021 Senior Notes, due 2041 Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Trade names Trade Names [Member] Financial Instruments Carried at Fair Value on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Award Type [Domain] Award Type [Domain] 2026 (After June 30,) Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year FAIR VALUE Fair Value Disclosures [Text Block] 2.00% 2021 Senior Notes, due 2031 2.00% 2021 Senior Notes, due 2031 [Member] 2.00% 2021 Senior Notes, due 2031 Transaction Type [Axis] Transaction Type [Axis] Expected holding period Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Treasury shares repurchased, inclusive of excise tax (in shares) Treasury Stock, Shares, Acquired Recurring Revenue Recurring Revenue [Member] Geographical [Axis] Geographical [Axis] Beginning Balance Ending Balance Contract with Customer, Liability Mutual funds Mutual Fund [Member] Internally developed software-related charges Internally Developed Software-Related Charges [Member] Internally Developed Software-Related Charges Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Treasury shares repurchased, inclusive of excise tax of $5 million Treasury Stock, Value, Acquired, Cost Method Payments for restructuring Cash payments Payments for Restructuring Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Schedule of Finite-Lived Intangible Assets [Table] Intangible Asset, Finite-Lived [Table] Professional service fees Accrued Professional Fees, Current Non-NEOs Non-NEOs [Member] Summary of Total Indebtedness Schedule of Debt [Table Text Block] LEASES Lessee, Operating Leases [Text Block] 2027 Long-Term Debt, Maturity, Year One Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Stock-Based Compensation Cost and Associated Tax Benefit Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block] Treasury shares Payments for Repurchase of Common Stock Deferred revenue Contract with Customer, Liability, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Gains and Losses on Derivatives Designated as Hedging Instruments Derivative Instruments, Gain (Loss) [Table Text Block] Operating Cost of Revenue Award Type [Axis] Award Type [Axis] Interest rate contracts Interest Rate Contract [Member] Contracts to sell EUR for USD Foreign Currency Forward Contracts To Sell Euros for US Dollars [Member] Foreign Currency Forward Contracts To Sell Euros for US Dollars Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Real Estate Real estate related costs Real Estate [Member] Retained earnings Retained Earnings (Accumulated Deficit) Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Product and Service [Axis] Product and Service [Axis] Fair Value Money market funds/mutual funds Equity Securities, FV-NI 2031 Net Investment Hedging Settlement Year Five [Member] Net Investment Hedging Settlement Year Five Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock, par value $0.01 per share Common Stock Common Stock [Member] Banking Banking [Member] Managed investments Managed investments [Member] Consists of revenue relating to managed investments. Segment Reporting, Operating Income (Loss) [Abstract] Segment Reporting, Operating Income (Loss) [Abstract] Operating lease cost Operating Lease, Cost Expected dividend yield Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Non-U.S. Non-US [Member] Derivative Contract [Domain] Derivative Contract [Domain] Net periodic pension income - non-service and non-interest cost components Net periodic pension costs - other components The total amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan, prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan and (3) expected return (loss) recognized in net periodic benefit cost, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Total liabilities, noncontrolling interests and shareholders' equity Liabilities and Equity Variable lease cost Variable Lease, Cost Estimated Annual Savings Estimated Annual Savings [Member] Estimated Annual Savings Employee Stock Option Share-Based Payment Arrangement, Option [Member] Foreign exchange forwards amount of gain (loss) recognized in income Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments Noncontrolling interests Equity, Attributable to Noncontrolling Interest Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Restructuring Total Restructuring Restructuring Charges Tabular List, Table Tabular List [Table Text Block] Bank loans Bank loans [Member] Consists of revenue relating to bank loans. 2030 Lessee, Operating Lease, Liability, to be Paid, after Year Four Lessee, Operating Lease, Liability, to be Paid, after Year Four Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Preferred stock, par value $0.01 per share; 10,000,000 shares authorized; no shares issued and outstanding Preferred Stock, Value, Issued Incentive compensation Accrued Bonuses, Current Adjustment to Compensation: Adjustment to Compensation [Axis] Amounts reclassified from AOCL Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Project and infrastructure Project and infrastructure [Member] Consists of revenue relating to project and infrastructure. Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activity Prepaid taxes Prepaid Taxes Public finance / sovereign Public finance/sovereign [Member] Consists of revenue relating to Public finance/sovereign. Contracts to sell USD for INR Foreign Currency Forward Contracts To Sell U.S. Dollars for Indian Rupees [Member] Foreign Currency Forward Contracts To Sell U.S. Dollars for Indian Rupees Hedging Designation [Axis] Hedging Designation [Axis] RESTRUCTURING Restructuring and Related Activities Disclosure [Text Block] Total Assets, Fair Value Disclosure Name Measure Name Pay vs Performance Disclosure [Line Items] Debt Debt [Member] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Capital Surplus Additional Paid-in Capital [Member] 4.875% 2018 Senior Notes, due 2048 4.875% 2018 Senior Notes, due 2048 [Member] Member related to 4.875% 2018 Notes, due 2048. Name Trading Arrangement, Individual Name Tax benefit realized upon vesting Employee Service Share Based Compensation Tax Benefit From Vesting of Other Than Stock Options Amount of tax benefit from vesting of other than stock options granted under share-based compensation arrangement. 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