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Operating Segment Information and Concentrations of Risk - Additional Information (Detail) - Customer | 12 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016 | Mar. 31, 2015
Segment Reporting Information [Line Items] |  |  |
Percentage of gross sales individually account for one customer | 10.00% | 10.00% | 10.00%
Number of customer | 1 |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 9.10% | 8.10% |
Net Sales [Member] | Geographic Concentration Risk [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Concentration risk, percentage | 21.00% | 22.00% | 25.00%

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