CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME
Reclassification adjustment for settled hedge contracts, income taxes	$ 91,870	$ 33,500	$ 65,734
Changes in fair value of hedge contracts, income taxes	(34,890)	(103,963)	(29,777)
Defined benefit pension and postretirement plans:
Net gain / (loss), income taxes	(815)	9,085	(3,245)
Plan termination and amendment, income taxes	0	0	(310)
Settlement, income taxes	0	(2,143)	(1,528)
Amortization of net obligation at transition, income taxes	0	(245)	(240)
Amortization of prior service cost, income taxes	(87)	(406)	(217)
Amortization of net loss, income taxes	(5,324)	(4,257)	(3,548)
Foreign currency translation adjustment, income taxes	$ 0	$ (34)	$ (20)

Tax effect of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

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