Income Taxes and Tax Receivable Agreement - Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2017	Aug. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Contingency [Line Items]
Tax expense (benefit) at U.S.federal statutory rate	$ 24,485
State income tax, net of U.S. federal tax benefit	1,685
Change in valuation allowance	529
Net income attributable to non-controlling interests	(13,872)
Changes in measurement of uncertain tax positions	(191)
Stock option compensation	306
Differences related to divested facilities	(429)
Nondeductible transaction costs	2,058
Tax return reconciling differences	0
Change in effective tax rate	64,343
TRA liability	(7,404)
Other	129
Total income tax expense (benefit)	$ 71,639
Predecessor
Income Tax Contingency [Line Items]
Tax expense (benefit) at U.S.federal statutory rate		$ 4,315	$ 32,263	$ (26,648)
State income tax, net of U.S. federal tax benefit		(456)	(86)	1,059
Change in valuation allowance		1,324	354	(137,721)
Net income attributable to non-controlling interests		(14,731)	(26,470)	(24,996)
Changes in measurement of uncertain tax positions		20	(262)	(10)
Stock option compensation		37	(200)	0
Differences related to divested facilities		(1,708)	0	0
Nondeductible transaction costs		(977)	0	3,442
Tax return reconciling differences		(316)	1,635	(1,574)
Change in effective tax rate		(825)	0	(2,143)
TRA liability		(4,782)	(327)	39,428
Other		10	188	181
Total income tax expense (benefit)		$ (18,089)	$ 7,095	$ (148,982)