Changes in Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)			$ (200,828)	$ (143,252)
Other comprehensive (loss) income before reclassifications to consolidated statements of income			77,785	1,560
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income			5,841	5,700
Net current-period other comprehensive (loss) income	$ 21,979	$ 2,882	83,626	7,260
Accumulated other comprehensive income (loss)	(117,202)	(135,992)	(117,202)	(135,992)
Gains and Losses on Cash Flow Hedges
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)			(227)	115
Other comprehensive (loss) income before reclassifications to consolidated statements of income			(501)	(823)
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income			377	243
Net current-period other comprehensive (loss) income			(124)	(580)
Accumulated other comprehensive income (loss)	(351)	(465)	(351)	(465)
Pension and Other Postretirement Benefit Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)			(114,570)	(105,703)
Other comprehensive (loss) income before reclassifications to consolidated statements of income			(1,888)	283
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income			5,464	5,457
Net current-period other comprehensive (loss) income			3,576	5,740
Accumulated other comprehensive income (loss)	(110,994)	(99,963)	(110,994)	(99,963)
Foreign Currency Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)			(86,031)	(37,664)
Other comprehensive (loss) income before reclassifications to consolidated statements of income			80,174	2,100
Amounts reclassified from accumulated other comprehensive income to the consolidated statements of income			0	0
Net current-period other comprehensive (loss) income			80,174	2,100
Accumulated other comprehensive income (loss)	$ (5,857)	$ (35,564)	$ (5,857)	$ (35,564)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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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-SubTopic 10
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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

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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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