Changes in Accumulated Other Comprehensive Income by Component (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	$ (99,453)	$ 25,944
Other comprehensive (loss) income before reclassifications to consolidated statements of income	(38,628)	(13,513)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	2,644	1,668
Net current-period other comprehensive loss	(35,984)	(11,845)
Accumulated other comprehensive income (loss)	(135,437)	14,099
Gains and Losses on Cash Flow Hedges
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	(732)	(519)
Other comprehensive (loss) income before reclassifications to consolidated statements of income	(201)	(146)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	313	119
Net current-period other comprehensive loss	112	(27)
Accumulated other comprehensive income (loss)	(620)	(546)
Pension and Other Postretirement Benefit Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	(115,289)	(73,273)
Other comprehensive (loss) income before reclassifications to consolidated statements of income	1,330	(7,419)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	2,331	1,549
Net current-period other comprehensive loss	3,661	(5,870)
Accumulated other comprehensive income (loss)	(111,628)	(79,143)
Foreign Currency Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	16,568	99,736
Other comprehensive (loss) income before reclassifications to consolidated statements of income	(39,757)	(5,948)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	0	0
Net current-period other comprehensive loss	(39,757)	(5,948)
Accumulated other comprehensive income (loss)	$ (23,189)	$ 93,788

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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