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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2018
Income Taxes Disclosure [Line Items] |  |  |
Benefit for income taxes | $ 424 | $ 283 |
Scenario Plan [Member] |  |  |
Income Taxes Disclosure [Line Items] |  |  |
GILTI tax rate |  |  | 10.50%

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- Definition Tax cuts and jobs act of 2017 global intangible low taxed income tax rate. + References No definition available. + Details
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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