Accumulated Other Comprehensive Income (Loss) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2017 USD ($)
Accumulated other comprehensive loss, tax
Accumulated other comprehensive loss at the beginning of the period	$ 9,544
Amounts reclassified from accumulated other comprehensive income (loss)	(340)
Current-period other comprehensive income (loss) activity	(2,605)
Accumulated other comprehensive loss at the end of the period	6,599
Accumulated other comprehensive loss, net of tax
Accumulated other comprehensive loss at the beginning of the period	(67,184)
Amounts reclassified from accumulated other comprehensive income (loss)	532
Current-period other comprehensive income (loss) activity	4,814
Accumulated other comprehensive loss at the end of the period	(61,838)
Cumulative Translation Adjustment [Member]
Accumulated other comprehensive loss, before tax
Accumulated other comprehensive loss at the beginning of the period	(31,942)
Amounts reclassified from accumulated other comprehensive income (loss)	0
Current-period other comprehensive income (loss) activity	7,362
Accumulated other comprehensive loss at the end of the period	(24,580)
Cash Flow Hedges [Member]
Accumulated other comprehensive loss, before tax
Accumulated other comprehensive loss at the beginning of the period	(826)
Amounts reclassified from accumulated other comprehensive income (loss)	451
Current-period other comprehensive income (loss) activity	57
Accumulated other comprehensive loss at the end of the period	(318)
Defined Benefit Plans [Member]
Accumulated other comprehensive loss, before tax
Accumulated other comprehensive loss at the beginning of the period	(43,960)
Amounts reclassified from accumulated other comprehensive income (loss)	421
Current-period other comprehensive income (loss) activity	0
Accumulated other comprehensive loss at the end of the period	$ (43,539)

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

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Tax adjustments of other comprehensive income (loss).

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Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, including portion attributable to noncontrolling interest. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

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Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) including portion attributable to noncontrolling interest.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount before tax of 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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