Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Net income	$ 6,620	$ 6,629	$ 12,902	$ 13,904
Cumulative translation adjustments	(254)	621	1,246	(2,215)
Pension and postretirement medical liability adjustments, net of tax	232	1,162	482	1,388
Other comprehensive (loss) income	(22)	1,783	1,728	(827)
Comprehensive income	$ 6,598	$ 8,412	$ 14,630	$ 13,077

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
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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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 of other comprehensive income (loss) attributable to parent entity.

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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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