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Income Taxes - Additional Information (Detail) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2018
Income Taxes [Line Items] |  |  |
Income tax benefit | $ (698,000) | $ (88,000) |
Effective income tax rate | 28.70% | (3.00%) |
Tax Cuts and Jobs Act, Measurement Period Adjustment, Income Tax Expense (Benefit) | $ 0 |  |
Settlement from Tax Audit [Member] |  |  |
Income Taxes [Line Items] |  |  |
Tax benefit recognized |  | $ 1,300,000 |
Anticipated [Member] |  |  |
Income Taxes [Line Items] |  |  |
Effective income tax rate |  |  | 31.00%

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- Definition Amount of income tax expense (benefit) for measurement period adjustment from accounting for tax effect pursuant to Tax Cuts and Jobs Act. + References No definition available. + Details
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- Definition Percentage 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 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 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)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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