CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME
Reclassification adjustment for settled hedge contracts, income taxes	$ 717	$ 28,263	$ 6,762	$ 49,863
Changes in fair value of hedge contracts, income taxes	(45,274)	(7,130)	(21,303)	(34,653)
Pension and postretirement benefits:
Amortization of prior service cost, income taxes	0	(43)	0	(86)
Amortization of net loss, income taxes	$ (81)	$ (2,647)	$ (161)	$ (5,294)

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Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

+ References

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-Publisher FASB

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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