CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest [Abstract]
Net income	$ 65,633us-gaap_ProfitLoss	$ 24,104us-gaap_ProfitLoss	$ 25,982us-gaap_ProfitLoss
Foreign currency translation adjustment	(16,473)	6,453	7,317
Unrealized loss on defined benefit plan, net of tax	(7,555)	(16,971)	(5,411)
Comprehensive income	41,605	13,586	27,888
Less: Comprehensive (income) loss attributable to noncontrolling interest	(1,955)	2,428	(1,830)
Total comprehensive income attributable to common stockholders	$ 39,650us-gaap_ComprehensiveIncomeNetOfTax	$ 16,014us-gaap_ComprehensiveIncomeNetOfTax	$ 26,058us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Glossary Comprehensive Income

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Topic 220

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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