Derivative Financial Instruments - Effect of Derivative Instruments (Detail) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ 180	$ (471)	$ (409)
Other (Income) Expense \| Foreign currency forward contracts
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in Income on Derivatives	$ 180	$ (471)	$ (409)

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Name:	us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration