Income Taxes - Schedule of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at April 1	$ 783	$ 905	$ 61
Additions for tax position of prior years	158	0	844
Reductions for tax positions of prior years	0	(122)	0
Balance at March 31	$ 941	$ 783	$ 905