Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 182,391us-gaap_ProfitLoss	$ 185,413us-gaap_ProfitLoss	$ 151,346us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Changes in net prior service credit and actuarial losses, net of tax (benefit) provision of $(28,408), $42,822 and $(3,337), respectively	(50,331)	66,754	(6,466)
Change in fair value of derivatives, net of tax provision (benefit) of $1,934, $2,763 and $(513), respectively	2,592	3,937	(905)
Foreign currency translation, net of tax (provision) benefit of $(14,027), $4,580 and $3,309, respectively	(79,766)	1,103	12,740
Other comprehensive (loss) income	(127,505)	71,794	5,369
Comprehensive income	$ 54,886us-gaap_ComprehensiveIncomeNetOfTax	$ 257,207us-gaap_ComprehensiveIncomeNetOfTax	$ 156,715us-gaap_ComprehensiveIncomeNetOfTax

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 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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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 other comprehensive income (loss).

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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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