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Components of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assets and Liabilities Eliminated upon Consolidation [Abstract]
Beginning balance, Foreign currency items	$ (92)	$ 1,173	$ 3,321
Current-period change, Foreign currency items	497	(1,265)	(2,148)
Ending balance, Foreign currency items	405	(92)	1,173
Beginning balance, Defined benefit pension plans	(693)	(678)	(678)
Current-period change, Defined benefit pension plans	(61)	(15)
Ending balance, Defined benefit pension plans	(754)	(693)	(678)
Beginning balance, Accumulated other comprehensive income (loss)	(785)	495	2,643
Current-period change, Accumulated other comprehensive income (loss)	436	(1,280)	(2,148)
Ending balance, Accumulated other comprehensive income (loss)	$ (349)	$ (785)	$ 495

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Assets and Liabilities Eliminated upon Consolidation [Abstract]

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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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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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