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Operating Segment Information and Concentrations of Risk - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Accounts Receivable | Customer A | Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	8.50%	9.00%
Sales Revenue, Net | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	36.00%	22.00%	21.00%

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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