Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Payables And Accruals [Abstract]
Accounts payable	$ 4,174	$ 7,146
Accrued miscellaneous expenses	9,419	9,142
Accrued VAT	1,517	809
Accrued outside services	2,744	2,251
Accrued subcontractor program costs	512	2,442
Accrued compensation	4,153	5,506
Income taxes payable	175	133
Accrued warranty	2,787	2,709
Total	$ 25,481	$ 30,138