Other Comprehensive Loss - After-tax Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Foreign currency translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ (24,313)	$ (21,079)
Net current period change	1,822	289
Reclassification adjustments for losses reclassified into income	0	0
Ending Balance	(22,491)	(20,790)
Pension and post-retirement benefits plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(24,532)	(18,575)
Reclassification adjustments for losses reclassified into income	(740)	109
Ending Balance	(25,272)	(18,466)
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(48,845)	(39,654)
Net current period change	1,822	289
Reclassification adjustments for losses reclassified into income	(740)	109
Ending Balance	$ (47,763)	$ (39,256)

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

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=66004921&loc=d3e1436-108581

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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