Stockholders' Equity - Summary of Noncontrolling Interest Balances (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance			$ 891,246	$ 944,262
Noncontrolling Interest, Increase from Business Combination			325,600
Distribution to noncontrolling interests			(9,164)	(8,187)
Other			(127)	(469)
Net loss	$ (28,904)	$ (12,423)	(32,018)	(17,801)
Other comprehensive loss, net of tax			(107)	(1,135)
Ending balance	1,175,430	916,670	1,175,430	916,670
Capital [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance			954,242	972,241
Noncontrolling Interest, Increase from Business Combination			325,600
Distribution to noncontrolling interests			(9,164)	(8,187)
Other			(127)	(469)
Net loss			0	0
Other comprehensive loss, net of tax			0	0
Ending balance	1,270,551	963,585	1,270,551	963,585
Accumulated Income (Loss) [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance			(62,614)	(27,426)
Noncontrolling Interest, Increase from Business Combination			0
Distribution to noncontrolling interests			0	0
Other			0	0
Net loss			(32,018)	(17,801)
Other comprehensive loss, net of tax			0	0
Ending balance	(94,632)	(45,227)	(94,632)	(45,227)
Accumulated Other Comprehensive Income [Member]
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance			(382)	(553)
Noncontrolling Interest, Increase from Business Combination			0
Distribution to noncontrolling interests			0	0
Other			0	0
Net loss			0	0
Other comprehensive loss, net of tax			(107)	(1,135)
Ending balance	$ (489)	$ (1,688)	$ (489)	$ (1,688)