CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income	$ 34,206us-gaap_ProfitLoss	$ 39,214us-gaap_ProfitLoss	$ 40,989us-gaap_ProfitLoss
Other comprehensive income (loss):
Change in unrecognized pension and post-retirement benefit costs	(1,820)	2,742	(157)
Tax (expense) benefit on change in unrecognized pension and post-retirement benefit costs	699	(974)	(10)
Foreign currency translation adjustments	(7,670)	(8,821)	(626)
Tax benefit on foreign currency translation adjustments	770	1,657	454
Other comprehensive loss	(8,021)	(5,396)	(339)
Comprehensive loss attributable to non-controlling interest	(565)	(236)	(15)
Comprehensive income attributable to controlling interest	$ 26,750us-gaap_ComprehensiveIncomeNetOfTax	$ 34,054us-gaap_ComprehensiveIncomeNetOfTax	$ 40,665us-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.

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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.

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Amount before tax, after 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 of tax expense (benefit), after 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 of other comprehensive income (loss) attributable to parent entity.

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

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Amount of tax (expense) benefit, after 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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