Income Taxes - Components of Comprehensive Provision for Income Taxes Allocation (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Comprehensive provision for income taxes allocable to:
Net income	$ 2,561	$ 3,330
Other comprehensive income:
Currency translation		700
Total	2,800	4,300
Defined Benefit Pension Plans
Other comprehensive income:
Defined benefit plans	$ 200	$ 300

Disclosure Other Comprehensive Income Loss Tax Effects Allocated To Component Of Other Comprehensive Income Loss.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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 reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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

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