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Income Taxes (Tables) | 12 Months Ended
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Dec. 31, 2011
Income Tax Disclosure [Abstract] |
Components of income (loss) before income taxes | The components of income (loss) before income taxes from continuing operations for each of the years ended December 31 were as follows:
| 2011 |  |  | 2010 |  |  | 2009 |
| (In thousands)
United States | $ | 333,486 |  |  | $ | 336,450 |  |  | $ | (227,021 | )
Foreign | 2,740 |  |  | 30,100 |  |  | 7,655 |
Income (loss) before income taxes from continuing operations | $ | 336,226 |  |  | $ | 366,550 |  |  | $ | (219,366 | )
Income tax expense (benefit) | Income tax expense (benefit) from continuing operations for the years ended December 31 was as follows:
| 2011 |  |  | 2010 |  |  | 2009 |
| (In thousands)
Current: |  |  |  |  |
Federal | $ | (7,188 | ) |  | $ | 37,014 |  |  | $ | 64,389 |
State | 778 |  |  | 10,589 |  |  | 8,284 |
Foreign | 127 |  |  | 4,451 |  |  | 254 |
| (6,283 | ) |  | 52,054 |  |  | 72,927 |
Deferred: |  |  |  |  |  |  |  |
Income taxes - |  |  |  |  |  |  |
Federal | 105,528 |  |  | 62,618 |  |  | (147,607 | )
State | 13,157 |  |  | 4,147 |  |  | (22,370 | )
Investment tax credit - net | 240 |  |  | (180 | ) |  | 213 |
| 118,925 |  |  | 66,585 |  |  | (169,764 | )
Change in uncertain tax benefits | (1,048 | ) |  | 3,230 |  |  | 562 |
Change in accrued interest | (1,320 | ) |  | 661 |  |  | 183 |
Total income tax expense (benefit) | $ | 110,274 |  |  | $ | 122,530 |  |  | $ | (96,092 | )
Deferred tax assets and deferred tax liabilities | Components of deferred tax assets and deferred tax liabilities at December 31 were as follows:
| 2011 |  |  | 2010 |
| (In thousands)
Deferred tax assets: |  |  |
Regulatory matters | $ | 119,189 |  |  | $ | 114,427 |
Accrued pension costs | 95,260 |  |  | 82,085 |
Asset retirement obligations | 26,380 |  |  | 24,391 |
Legal and environmental contingencies | 21,788 |  |  | 13,622 |
Compensation-related | 16,241 |  |  | 17,261 |
Other | 41,055 |  |  | 40,307 |
Total deferred tax assets | 319,913 |  |  | 292,093 |
Deferred tax liabilities: |  |  |  |  |
Depreciation and basis differences on property, plant and equipment | 715,482 |  |  | 679,809 |
Basis differences on natural gas and oil producing properties | 210,146 |  |  | 152,455 |
Regulatory matters | 84,963 |  |  | 64,017 |
Intangible asset amortization | 14,307 |  |  | 14,843 |
Other | 23,774 |  |  | 20,348 |
Total deferred tax liabilities | 1,048,672 |  |  | 931,472 |
Net deferred income tax liability | $ | (728,759 | ) |  | $ | (639,379 | )
Schedule of Change in Net Deferred Income Tax Liability Reconciliation [Table Text Block] | The following table reconciles the change in the net deferred income tax liability from December 31, 2010, to December 31, 2011, to deferred income tax expense:
| 2011 |
(In thousands) |
Change in net deferred income tax liability from the preceding table | $ | 89,380 |
Deferred taxes associated with other comprehensive loss | 9,678 |
Deferred taxes associated with discontinued operations | 8,090 |
Other | 11,777 |
Deferred income tax expense for the period | $ | 118,925 |
Reconciliation of income tax expense (benefit) at statutory federal rate versus actual rate | Total income tax expense (benefit) differs from the amount computed by applying the statutory federal income tax rate to income (loss) before taxes. The reasons for this difference were as follows:
Years ended December 31, | 2011 |  | 2010 |  | 2009
| Amount |  |  | % |  |  | Amount |  |  | % |  |  | Amount |  |  | % |
| (Dollars in thousands)
Computed tax at federal statutory rate | $ | 117,679 |  |  | 35.0 |  |  | $ | 128,293 |  |  | 35.0 |  |  | $ | (76,778 | ) |  | 35.0 |
Increases (reductions) resulting from: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
State income taxes, net of federal income tax benefit (expense) | 10,653 |  |  | 3.2 |  |  | 10,210 |  |  | 2.8 |  |  | (7,280 | ) |  | 3.3 |
Resolution of tax matters and uncertain tax positions | (3,906 | ) |  | (1.2 | ) |  | 667 |  |  | .2 |  |  | 881 |  |  | (.4 | )
Federal renewable energy credit | (3,485 | ) |  | (1.0 | ) |  | (2,185 | ) |  | (.6 | ) |  | (1,452 | ) |  | .7 |
Depletion allowance | (3,266 | ) |  | (1.0 | ) |  | (2,810 | ) |  | (.8 | ) |  | (2,320 | ) |  | 1.0 |
Deductible K-Plan dividends | (2,282 | ) |  | (.7 | ) |  | (2,309 | ) |  | (.6 | ) |  | (2,369 | ) |  | 1.1 |
Foreign operations | (391 | ) |  | (.1 | ) |  | (588 | ) |  | (.2 | ) |  | (1,148 | ) |  | .5 |
Domestic production activities deduction | — |  |  | — |  |  | — |  |  | — |  |  | (856 | ) |  | .4 |
Other | (4,728 | ) |  | (1.4 | ) |  | (8,748 | ) |  | (2.4 | ) |  | (4,770 | ) |  | 2.2 |
Total income tax expense (benefit) | $ | 110,274 |  |  | 32.8 |  |  | $ | 122,530 |  |  | 33.4 |  |  | $ | (96,092 | ) |  | 43.8 |
Reconciliation of unrecognized tax benefits (excluding interest) | A reconciliation of the unrecognized tax benefits (excluding interest) for the years ended December 31 was as follows:
| 2011 |  |  | 2010 |  |  | 2009 |
| (In thousands)
Balance at beginning of year | $ | 9,378 |  |  | $ | 6,148 |  |  | $ | 5,586 |
Additions for tax positions of prior years | 4,172 |  |  | 3,230 |  |  | 562 |
Settlements | (2,344 | ) |  | — |  |  | — |
Balance at end of year | $ | 11,206 |  |  | $ | 9,378 |  |  | $ | 6,148 |

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- Definition Tabular disclosure of tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities (i.e., uncertain tax positions) and other types of income tax contingencies, including: (1) the policy on classification of interest and penalties; (2) a tabular reconciliation of the total amounts of unrecognized tax benefits at the beginning and end of the period; the total amount(s) of: (3) unrecognized tax benefits that, if recognized, would affect the effective tax rate, and (4) interest and penalties recognized in each of the income statement and balance sheet; (5) for positions for which it is reasonably possible that the total amounts unrecognized will significantly change within 12 months of the reporting date the: (i) nature of the uncertainty, (ii) nature of the event that could occur that would cause the change, and (iii) an estimate of the range of the reasonably possible change or a statement that an estimate of the range cannot be made; and (6) a description of tax years that remain subject to examination by major tax jurisdictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 48 -Paragraph 21 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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