Changes in Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	$ (143,252)	$ (99,453)
Other comprehensive (loss) income before reclassifications to consolidated statements of income	20,038	(38,628)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	1,845	2,644
Net current-period other comprehensive income (loss)	21,883	(35,984)
Accumulated other comprehensive income (loss)	(121,369)	(135,437)
Gains and Losses on Cash Flow Hedges
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	115	(732)
Other comprehensive (loss) income before reclassifications to consolidated statements of income	(239)	(201)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	91	313
Net current-period other comprehensive income (loss)	(148)	112
Accumulated other comprehensive income (loss)	(33)	(620)
Pension and Other Postretirement Benefit Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	(105,703)	(115,289)
Other comprehensive (loss) income before reclassifications to consolidated statements of income	(436)	1,330
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	1,754	2,331
Net current-period other comprehensive income (loss)	1,318	3,661
Accumulated other comprehensive income (loss)	(104,385)	(111,628)
Foreign Currency Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	(37,664)	16,568
Other comprehensive (loss) income before reclassifications to consolidated statements of income	20,713	(39,757)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income	0	0
Net current-period other comprehensive income (loss)	20,713	(39,757)
Accumulated other comprehensive income (loss)	$ (16,951)	$ (23,189)

Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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-Publisher SEC
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-Paragraph 31
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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

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