Summary of Significant Accounting Policies - Equipment Under Capital Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Mar. 31, 2016
Property, Plant and Equipment [Line Items]
Equipment	$ 33,300	$ 35,581
Less: accumulated depreciation and amortization	(19,251)	(18,577)
Property and equipment, net	14,049	17,004
Assets Held under Capital Leases
Property, Plant and Equipment [Line Items]
Equipment	581	408
Less: accumulated depreciation and amortization	(131)	(65)
Property and equipment, net	$ 450	$ 343