Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net income	$ 6,345	$ 8,352
Other comprehensive income (loss):
Foreign currency translation adjustment	842	110
Cumulative effect of accounting change	0	(350)
Minimum pension and post retirement benefit plan adjustments	12	27
Other comprehensive income (loss)	854	(213)
Total comprehensive income	$ 7,199	$ 8,139

Other Comprehensive (Income) Loss, Minimum Pension Liability Net Adjustment Net Of Tax

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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, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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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 other comprehensive income (loss).

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