Consolidated Statement Stockholders' and Members Equity (Deficit) - USD ($) $ in Thousands	Member Unit	Members' Deficit	Additional Paid-in Capital	Retained Earnings (Deficit)	Non-controlling Interest	Class A common stock	Class B common stock	Class C common stock	Total
Balance at Dec. 31, 2014		$ (250,675)							$ (250,675)
Balance (in shares) at Dec. 31, 2014	154,401
Increase (Decrease) in Members' Equity (Deficit)
Members' distributions		(230,777)							(230,777)
Net income		174,293							174,293
Balance at Dec. 31, 2015		(307,159)							(307,159)
Balance (in shares) at Dec. 31, 2015	155,559
Increase (Decrease) in Members' Equity (Deficit)
Membership units, issued (in shares)	1,158
Net income prior to the Reorganization Transactions (Restated)		189,531							189,531
Membership units redeemed prior to the Reorganization Transactions		(17,000)							(17,000)
Membership units redeemed prior to the Reorganization Transactions (in shares)	(1,763)
Members' distributions prior to the Reorganization Transactions		(197,922)							(197,922)
Non-cash distributions prior to the Reorganization Transactions		(38,838)							(38,838)
Equity-based compensation recognized prior to the Reorganization Transactions		949							949
Effect of the Reorganization Transactions (Restated)		$ 370,439	$ (21,887)		$ (334,047)	$ 71	$ 6		14,582
Effect of the Reorganization Transactions (Restated) (in shares)	(153,796)					7,064,000	62,003,000
Issuance of Class A common stock sold in a public offering, net of underwriting discounts, commissions and offering costs			233,958			$ 118			234,076
Issuance of Class A common stock sold in a public offering, net of underwriting discounts, commissions and offering costs (in shares)						11,872,000
Non-controlling interest adjustment for purchase of common units from CWGS, LLC with proceeds from a public offering			(234,486)		234,486
Equity-based compensation recognized subsequent to Reorganization Transactions			648						648
Distributions to holders of LLC Units					(21,223)				(21,223)
Dividends				$ (1,515)					(1,515)
Establishment of liabilities under the Tax Receivable Agreement and related changes to deferred tax assets associated with that liability			(11,794)						(11,794)
Non-controlling interest adjustment			3,555		(3,555)
Net income subsequent to the Reorganization Transactions				1,586	9,942				11,528
Net income						$ 11,528			201,059
Balance at Dec. 31, 2016			(30,006)	71	(114,397)	$ 189	$ 6		(144,137)
Balance (in shares) at Dec. 31, 2016						18,935,916	62,002,729	1
Increase (Decrease) in Members' Equity (Deficit)
Issuance of Class A common stock sold in a public offering, net of underwriting discounts, commissions and offering costs			121,203			$ 46			121,249
Issuance of Class A common stock sold in a public offering, net of underwriting discounts, commissions and offering costs (in shares)						4,600,000
Non-controlling interest adjustment for purchase of common units from CWGS, LLC with proceeds from a public offering			(87,203)		87,203
Issuance of Class A common stock for an acquisition by a subsidiary			5,719			$ 1			5,720
Issuance of Class A common stock for an acquisition by a subsidiary (in shares)						164,000
Non-controlling interest adjustment for capital contribution of Class A common stock for an acquisition by a subsidiary			(3,678)		3,678
Equity-based compensation			5,109						5,109
Exercise of stock options			1,731			$ 1			1,732
Exercise of stock options (in shares)						80,000
Non-controlling interest adjustment for capital contribution of proceeds from the exercise of stock options			(970)		970
Vesting of restricted stock units			257		(257)
Vesting of restricted stock units (in shares)						33,000
Repurchases of Class A common stock for withholding taxes on vested RSUs			368						368
Repurchases of Class A common stock for withholding taxes on vested RSUs (in shares)						(9,000)
Redemption of LLC common units for Class A common stock			175,487		(881)	$ 130	$ (1)		174,735
Redemption of LLC common units for Class A common stock (in shares)						12,945,000	(11,166,000)
Distributions to holders of LLC Units					(149,633)				(149,633)
Dividends				(22,241)					(22,241)
Establishment of liabilities under the Tax Receivable Agreement and related changes to deferred tax assets associated with that liability			(134,303)						(134,303)
Non-controlling interest adjustment			(3,037)		3,037
Net income				28,362	204,612	$ 232,974			232,974
Balance at Dec. 31, 2017			$ 49,941	$ 6,192	$ 34,332	$ 367	$ 5		$ 90,837
Balance (in shares) at Dec. 31, 2017						36,749,072	50,836,629	1