Schedule of Deferred Stock Unit Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Deferred Stock Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense (benefit)	$ (904)	$ (2,477)	$ 1,737

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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