Amounts Charged to Expense Related to Defined Contribution Plans (Detail) - Defined Contribution Savings Plan 401k - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plans expense, net of forfeitures	$ 2,660	$ 3,443	$ 4,216
Defined contribution plans forfeitures	$ 149	$ 202	$ 52

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.

No definition available.

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