Reconciliation of Income Taxes Computed at U.S. Federal Statutory Rate to Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
	Jun. 30, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Income tax expense at statutory rate		$ 15,747	$ 5,211	$ 3,056
State income taxes		8,038	2,522	251
Deferred tax impact of reorganization		(2,382)
Nondeductible transaction costs			1,148
Tax benefit of partnership status			(726)	(2,211)
Valuation allowance reversal			(502)
Foreign rate differential		(253)	(220)	(188)
All other		(429)	709	(95)
Total income tax expense	$ (8,100)	$ 20,721	$ 8,142	$ 813