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Fair Value Measurements - Additional Information (Detail) $ in Millions	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017 Contract	Mar. 31, 2017 USD ($) Contract
Fair Value Disclosures [Abstract]
Cash equivalents maturity period, days	90 days	90 days
Number of contracts outstanding | Contract		0
Predecessor
Fair Value Disclosures [Abstract]
Number of contracts outstanding | Contract			6
Notional value of foreign exchange contract | $			$ 1.5
Predecessor | Forward Contracts
Fair Value Disclosures [Abstract]
Gain (loss) on Derivatives | $			$ (0.7)

X

- Definition

Notional value equivalent of forward contract.

+ References

No definition available.

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- Definition

Short term deposits maximum maturity period.

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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