Consolidated Statements of 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
Increase (Decrease) in Members' Equity (Deficit)
Membership units, issued (in shares)		155,559,000
Balance at Dec. 31, 2015			$ (321,445)							$ (321,445)
Increase (Decrease) in Members' Equity (Deficit)
Net income prior to the Reorganization Transactions (Restated)			187,363							187,363
Membership units redeemed prior to the Reorganization Transactions			(17,000)							(17,000)
Membership units redeemed prior to the Reorganization Transactions (in shares)		(1,763,000)
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)			$ 386,893	$ (23,504)		$ (348,885)	$ 71	$ 6		14,581
Effect of the Reorganization Transactions (Restated) (in shares)		(153,796,000)					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 common units						(21,223)				(21,223)
Dividends subsequent to the Reorganization Transactions	[1]				$ (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				1,452		(1,452)
Net income subsequent to the Reorganization Transactions					1,522	9,591				11,113
Net income							$ 11,113			198,476
Balance at Dec. 31, 2016				(33,726)	7	(127,483)	$ 189	$ 6		(161,007)
Balance (in shares) at Dec. 31, 2016							18,936,000	62,003,000
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
Non-controlling interest adjustment for capital contribution of Class A common stock for an acquisition by a subsidiary				(3,678)		3,678
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
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				177,747		(881)	$ 130	$ (1)		176,995
Redemption of LLC common units for Class A common stock (in shares)							12,945,000	(11,166,000)
Distributions to holders of LLC common units						(149,633)				(149,633)
Dividends	[1]				(22,241)					(22,241)
Establishment of liabilities under the Tax Receivable Agreement and related changes to deferred tax assets associated with that liability				(136,485)						(136,485)
Non-controlling interest adjustment				(6,816)		6,816
Net income					29,853	200,839	$ 230,692			230,692
Balance at Dec. 31, 2017				42,520	7,619	21,252	$ 367	$ 5		71,763
Balance (in shares) at Dec. 31, 2017							36,749,072	50,836,629	1
Increase (Decrease) in Members' Equity (Deficit)
Equity-based compensation				14,088						14,088
Exercise of stock options				149						149
Exercise of stock options (in shares)							7,000
Non-controlling interest adjustment for capital contribution of proceeds from the exercise of stock options				(86)		86
Vesting of restricted stock units				881		(884)	$ 3
Vesting of restricted stock units (in shares)							298,000
Repurchases of Class A common stock for withholding taxes on vested RSUs				(1,364)			$ (1)			(1,365)
Repurchases of Class A common stock for withholding taxes on vested RSUs (in shares)							(77,000)
Disgorgement of short-swing profits by Section 16 officer				557						557
Redemption of LLC common units for Class A common stock				4,536		(153)	$ 3			4,386
Redemption of LLC common units for Class A common stock (in shares)							215,000	(130,000)
Distributions to holders of LLC common units						(101,755)				(101,755)
Dividends	[1]				(22,697)					(22,697)
Establishment of liabilities under the Tax Receivable Agreement and related changes to deferred tax assets associated with that liability				(1,576)						(1,576)
Non-controlling interest adjustment				(12,174)		12,174
Net income					10,398	55,183	$ 65,581			65,581
Balance at Dec. 31, 2018				$ 47,531	(3,370)	(11,621)	$ 372	$ 5		32,917
Balance (in shares) at Dec. 31, 2018							37,192,364	50,706,629	1
Increase (Decrease) in Members' Equity (Deficit)
Adoption of accounting standard (see Note 1 - Summary of Significant Accounting Policies) | ASU 2014-09					$ 1,310	$ 2,476				$ 3,786

[1] The Company declared dividends per share of Class A common stock of $0.61, $0.74, and $0.08 per share in 2018, 2017, and 2016, respectively.