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Fair Value Measurements and Disclosures - Additional Information (Detail) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 Contract | Mar. 31, 2017 USD ($) Contract
Derivatives, Fair Value [Line Items] |  |
Cash equivalents maturity period, days | 90 days |
Number of contracts outstanding | Contract | 0 |
Predecessor |  |
Derivatives, Fair Value [Line Items] |  |
Number of contracts outstanding | Contract |  | 6
Notional value of foreign exchange contract | $ |  | $ 1.5
Predecessor | Forward Contracts |  |
Derivatives, Fair Value [Line Items] |  |
Gain (loss) on Derivatives | $ |  | $ 0.7

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- Definition The number of derivative instruments of a particular group held by the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959 + Details
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- Definition The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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