001 - Statement - Condensed Consolidated Statements of Financial Position (Unaudited) link:presentationLink link:definitionLink link:calculationLink 002 - Statement - Condensed Consolidated Statements of Financial Position (Unaudited) (Parentheticals) link:presentationLink link:definitionLink link:calculationLink 003 - Statement - Condensed Consolidated Statements of Income (Unaudited) link:presentationLink link:definitionLink link:calculationLink 004 - Statement - Condensed Consolidated Statements of Income (Unaudited) (Parentheticals) link:presentationLink link:definitionLink link:calculationLink 005 - Statement - Condensed Consolidated Statements of Comprehensive Income (Unaudited) link:presentationLink link:definitionLink link:calculationLink 006 - Statement - Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parentheticals) link:presentationLink link:definitionLink link:calculationLink 007 - Statement - Condensed Consolidated Statements of Equity (Unaudited) link:presentationLink link:definitionLink link:calculationLink 008 - Statement - Condensed Consolidated Statements of Equity (Unaudited) (Parentheticals) link:presentationLink link:definitionLink link:calculationLink 009 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited) link:presentationLink link:definitionLink link:calculationLink 010 - Disclosure - Note 1 - Organization and Basis of Presentation link:presentationLink link:definitionLink link:calculationLink 011 - Disclosure - Note 2 - Significant Accounting Policies and Methods of Application link:presentationLink link:definitionLink link:calculationLink 012 - Disclosure - Note 3 - Regulated Operations link:presentationLink link:definitionLink link:calculationLink 013 - Disclosure - Note 4 - Fair Value Measurements link:presentationLink link:definitionLink link:calculationLink 014 - Disclosure - Note 5 - Derivative Instruments link:presentationLink link:definitionLink link:calculationLink 015 - Disclosure - Note 6 - Employee Benefit Plans link:presentationLink link:definitionLink link:calculationLink 016 - Disclosure - Note 7 - Debt and Credit Facilities link:presentationLink link:definitionLink link:calculationLink 017 - Disclosure - Note 8 - Equity link:presentationLink link:definitionLink link:calculationLink 018 - Disclosure - Note 9 - Non-Wholly Owned Entities link:presentationLink link:definitionLink link:calculationLink 019 - Disclosure - Note 10 - Commitments, Guarantees and Contingencies link:presentationLink link:definitionLink link:calculationLink 020 - Disclosure - Note 11 - Segment Information link:presentationLink link:definitionLink link:calculationLink 021 - Disclosure - Note 12 - Discontinued Operations link:presentationLink link:definitionLink link:calculationLink 022 - Disclosure - Note 13 - Subsequent Events link:presentationLink link:definitionLink link:calculationLink 023 - Disclosure - Accounting Policies, by Policy (Policies) link:presentationLink link:definitionLink link:calculationLink 024 - Disclosure - Note 2 - Significant Accounting Policies and Methods of Application (Tables) link:presentationLink link:definitionLink link:calculationLink 025 - Disclosure - Note 3 - Regulated Operations (Tables) link:presentationLink link:definitionLink link:calculationLink 026 - Disclosure - Note 4 - Fair Value Measurements (Tables) link:presentationLink link:definitionLink link:calculationLink 027 - Disclosure - Note 5 - Derivative Instruments (Tables) link:presentationLink link:definitionLink link:calculationLink 028 - Disclosure - Note 6 - Employee Benefit Plans (Tables) link:presentationLink link:definitionLink link:calculationLink 029 - Disclosure - Note 7 - Debt and Credit Facilities (Tables) link:presentationLink link:definitionLink link:calculationLink 030 - Disclosure - Note 8 - Equity (Tables) link:presentationLink link:definitionLink link:calculationLink 031 - Disclosure - Note 9 - Non-Wholly Owned Entities (Tables) link:presentationLink link:definitionLink link:calculationLink 032 - Disclosure - Note 11 - Segment Information (Tables) link:presentationLink link:definitionLink link:calculationLink 033 - Disclosure - Note 12 - Discontinued Operations (Tables) link:presentationLink link:definitionLink link:calculationLink 034 - Disclosure - Note 2 - Significant Accounting Policies and Methods of Application (Details) link:presentationLink link:definitionLink link:calculationLink 035 - Disclosure - Note 2 - Significant Accounting Policies and Methods of Application (Details) - Changes in Amount of Goodwill link:presentationLink link:definitionLink link:calculationLink 036 - Disclosure - Note 2 - Significant Accounting Policies and Methods of Application (Details) - Other Income link:presentationLink link:definitionLink link:calculationLink 037 - Disclosure - Note 2 - Significant Accounting Policies and Methods of Application (Details) - Potentially Dilutive Common Share Calculation link:presentationLink link:definitionLink link:calculationLink 038 - Disclosure - Note 3 - Regulated Operations (Details) link:presentationLink link:definitionLink link:calculationLink 039 - Disclosure - Note 3 - Regulated Operations (Details) - Summary of Regulatory Assets and Liabilities link:presentationLink link:definitionLink link:calculationLink 040 - Disclosure - Note 3 - Regulated Operations (Details) - Change in Net Position of Deferred and Accrued Natural Gas Costs link:presentationLink link:definitionLink link:calculationLink 041 - Disclosure - Note 3 - Regulated Operations (Details) - Costs Related to Remediation of Former Operating Sites link:presentationLink link:definitionLink link:calculationLink 042 - Disclosure - Note 4 - Fair Value Measurements (Details) link:presentationLink link:definitionLink link:calculationLink 043 - Disclosure - Note 4 - Fair Value Measurements (Details) - Derivative Assets and Liabilities link:presentationLink link:definitionLink link:calculationLink 044 - Disclosure - Note 4 - Fair Value Measurements (Details) - Amortized Cost and Fair Value of Long-Term Debt link:presentationLink link:definitionLink link:calculationLink 045 - Disclosure - Note 5 - Derivative Instruments (Details) link:presentationLink link:definitionLink link:calculationLink 046 - Disclosure - Note 5 - Derivative Instruments (Details) - Net Long Natural Gas Contracts link:presentationLink link:definitionLink link:calculationLink 047 - Disclosure - Note 5 - Derivative Instruments (Details) - Gains and Losses on Derivative Instruments link:presentationLink link:definitionLink link:calculationLink 048 - Disclosure - Note 5 - Derivative Instruments (Details) - Derivative Instruments on the Condensed Consolidated Statements of Financial Position link:presentationLink link:definitionLink link:calculationLink 049 - Disclosure - Note 5 - Derivative Instruments (Details) - Derivative Instruments on the Consolidated Statements of Income link:presentationLink link:definitionLink link:calculationLink 050 - Disclosure - Note 6 - Employee Benefit Plans (Details) - Components of Pension and Other Retirement Benefit Costs link:presentationLink link:definitionLink link:calculationLink 051 - Disclosure - Note 7 - Debt and Credit Facilities (Details) link:presentationLink link:definitionLink link:calculationLink 052 - Disclosure - Note 7 - Debt and Credit Facilities (Details) - Debt Schedule link:presentationLink link:definitionLink link:calculationLink 053 - Disclosure - Note 7 - Debt and Credit Facilities (Details) - Debt-to-Capitalization Ratios link:presentationLink link:definitionLink link:calculationLink 054 - Disclosure - Note 8 - Equity (Details) - Other Comprehensive Income (Loss) link:presentationLink link:definitionLink link:calculationLink 055 - Disclosure - Note 8 - Equity (Details) - Reclassifications Out of Accumulated Other Comprehensive Loss link:presentationLink link:definitionLink link:calculationLink 056 - Disclosure - Note 9 - Non-Wholly Owned Entities (Details) link:presentationLink link:definitionLink link:calculationLink 057 - Disclosure - Note 9 - Non-Wholly Owned Entities (Details) - SouthStar’s Assets and Liabilities link:presentationLink link:definitionLink link:calculationLink 058 - Disclosure - Note 9 - Non-Wholly Owned Entities (Details) - SouthStar’s Revenues and Expenses link:presentationLink link:definitionLink link:calculationLink 059 - Disclosure - Note 9 - Non-Wholly Owned Entities (Details) - Equity Method Investments link:presentationLink link:definitionLink link:calculationLink 060 - Disclosure - Note 9 - Non-Wholly Owned Entities (Details) - Income from Equity Method Investments link:presentationLink link:definitionLink link:calculationLink 061 - Disclosure - Note 10 - Commitments, Guarantees and Contingencies (Details) link:presentationLink link:definitionLink link:calculationLink 062 - Disclosure - Note 11 - Segment Information (Details) link:presentationLink link:definitionLink link:calculationLink 063 - Disclosure - Note 11 - Segment Information (Details) - Segment Reporting link:presentationLink link:definitionLink link:calculationLink 064 - Disclosure - Note 11 - Segment Information (Details) - Intersegment Reporting link:presentationLink link:definitionLink link:calculationLink 065 - Disclosure - Note 11 - Segment Information (Details) - Operating Revenues link:presentationLink link:definitionLink link:calculationLink 066 - Disclosure - Note 12 - Discontinued Operations (Details) link:presentationLink link:definitionLink link:calculationLink 067 - Disclosure - Note 12 - Discontinued Operations (Details) - Assets and Liabilities of Tropical Shipping link:presentationLink link:definitionLink link:calculationLink 068 - Disclosure - Note 12 - Discontinued Operations (Details) - Discontinued Operations from Statement of Income link:presentationLink link:definitionLink link:calculationLink 069 - Disclosure - Note 13 - Subsequent Events (Details) link:presentationLink link:definitionLink link:calculationLink 000 - Disclosure - Document And Entity Information link:presentationLink link:definitionLink link:calculationLink