Property and Equipment - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Mar. 31, 2017
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 110,727	$ 97,908
Less: accumulated depreciation and amortization	(57,199)	(47,180)
Total property and equipment, net	53,528	50,728
Computers, software, and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	7,859	7,060
Site operation equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	35,520	25,874
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment	1,838	1,770
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	31,140	30,586
Capitalized software development costs
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 34,370	$ 32,618