Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 44,003	$ 59,529	$ 75,479	$ 84,962
Other comprehensive income (loss), net of tax:
Changes in net prior service credit and actuarial losses	(133)	1,718	(544)	3,759
Change in fair value of derivatives	523	1,398	1,338	2,861
Foreign currency translation	3,160	(4,544)	(7,088)	(16,589)
Other comprehensive income (loss)	3,550	(1,428)	(6,294)	(9,969)
Comprehensive income	$ 47,553	$ 58,101	$ 69,185	$ 74,993

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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

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