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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

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Data Type:	num:percentItemType
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Period Type:	duration

Segment and Enterprise Wide Disclosures - Additional Information (Detail) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016	Sep. 30, 2017 USD ($) Segment	Sep. 30, 2016	Mar. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of business segments \| Segment			1
International
Segment Reporting Information [Line Items]
Long-lived assets \| $	$ 28.9		$ 28.9		$ 23.2
Customer Concentration Risk \| Product Revenue \| International
Segment Reporting Information [Line Items]
Percentage of revenue accounted	11.00%	9.00%	10.00%	9.00%