Schedule II - Valuation Accounts (Detail) - USD ($) $ in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Apr. 30, 2014
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period		$ 988	$ 2,153
Balance at end of period	$ 2,153		988
Allowance for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	1,672	988	2,153	$ 1,332
Additions—charged to expense	1,524	1,107	1,344	1,586
Deductions—bad debts written off, net of recoveries	(1,043)	(1,026)	(2,509)	(1,246)
Balance at end of period	$ 2,153	$ 1,069	$ 988	$ 1,672