Earnings (loss) from equity method investments, tax.

No definition available.

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Glossary Income Tax Expense (or Benefit)

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Reclassifications out of accumulated other comprehensive (loss) (Details 15) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reclassification adjustment out of accumulated other comprehensive income
Operating revenues	$ 1,163,204us-gaap_Revenues	$ 1,370,455us-gaap_Revenues	$ 1,094,046us-gaap_Revenues	$ 1,042,853us-gaap_Revenues	$ 1,184,423us-gaap_Revenues	$ 1,285,782us-gaap_Revenues	$ 1,060,595us-gaap_Revenues	$ 931,604us-gaap_Revenues	$ 4,670,558us-gaap_Revenues	$ 4,462,404us-gaap_Revenues	$ 4,075,431us-gaap_Revenues
Interest expense									(87,016)us-gaap_InterestExpense	(83,917)us-gaap_InterestExpense	(76,699)us-gaap_InterestExpense
Income (loss) before income taxes									411,130	415,618	(45,467)
Income taxes									(119,969)us-gaap_IncomeTaxExpenseBenefit	(136,736)us-gaap_IncomeTaxExpenseBenefit	31,146us-gaap_IncomeTaxExpenseBenefit
Net income (loss)									294,338us-gaap_ProfitLoss	278,570us-gaap_ProfitLoss	(754)us-gaap_ProfitLoss
Earnings (loss) from equity method investments									(41)	(132)	5,383
Reclassification adjustment for gain (loss) on derivative instruments included in net income
Reclassification adjustment out of accumulated other comprehensive income
Income (loss) before income taxes									(1,107)	6,737
Income taxes									413	(2,548)
Net income (loss)									(694)	4,189
Amortization of postretirement liability losses included in net periodic benefit cost
Reclassification adjustment out of accumulated other comprehensive income
Income taxes									492	1,276
Net income (loss)									(796)	(2,001)
Net periodic benefit cost									(1,288)	(3,277)
Reclassification adjustment for loss on foreign currency translation adjustment included in net income
Reclassification adjustment out of accumulated other comprehensive income
Net income (loss)									0	(143)
Earnings (loss) from equity method investments									0	(213)
Earnings (loss) from equity method investments, tax									0	70
Reclassification adjustment for loss on available-for-sale investments included in net income [Member]
Reclassification adjustment out of accumulated other comprehensive income
Income taxes									73	59
Net income (loss)									(135)	(109)
Other income									(208)	(168)
Total reclassifications
Reclassification adjustment out of accumulated other comprehensive income
Net income (loss)									(1,625)	1,936
Commodity derivative instruments [Member] \| Reclassification adjustment for gain (loss) on derivative instruments included in net income
Reclassification adjustment out of accumulated other comprehensive income
Operating revenues									(468)	7,803
Interest rate derivative instruments [Member] \| Reclassification adjustment for gain (loss) on derivative instruments included in net income
Reclassification adjustment out of accumulated other comprehensive income
Interest expense									$ (639)	$ (1,066)