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Income Taxes - Valuation Allowance (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Income Tax Disclosure [Abstract] |  |
Beginning valuation allowance | $ 137,976 | $ 140,117
Increase (decrease) as reflected in income tax expense | 12,453 | (114)
Cumulative translation adjustment | 10,412 | (2,027)
Ending valuation allowance | $ 160,841 | $ 137,976

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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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