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Fair Value Measurements - Additional Information (Detail) $ in Millions | 6 Months Ended |
--- | --- | ---
Sep. 30, 2017 USD ($) Contract | Mar. 31, 2017 USD ($) Contract
Derivatives, Fair Value [Line Items] |  |
Cash equivalents maturity period, days | 90 days |
Number of contracts outstanding | Contract | 44 |
Notional value of foreign exchange contract | $ | $ 1.9 |
Predecessor |  |
Derivatives, Fair Value [Line Items] |  |
Number of contracts outstanding | Contract |  | 6
Notional value of foreign exchange contract | $ |  | $ 1.5

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