Income Taxes (Restated) - Federal Tax purpose (Details) - USD ($) $ in Thousands			3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Oct. 06, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Effective tax rate			8.90%	3.20%	10.50%	2.40%
Federal statutory rate					35.00%	35.00%
Uncertain tax positions	$ 0		$ 0		$ 0		$ 0
Interest or penalties relating to income taxes			0	$ 0	0	$ 0
Payment, as percent of tax benefits (as a percent)		85.00%
Current portion of liabilities under tax receivable agreement	$ 7,378		$ 7,378		$ 7,378		$ 991
Tax receivable agreement
Expected future tax benefits retained by the Company (as a percent)		15.00%
Tax receivable agreement | Continuing Equity Owners and Crestview partners II GP LP
Payment, as percent of tax benefits (as a percent)		85.00%
CWGS, LLC | Tax receivable agreement
Units issued in exchange			1,001,248		6,526,610
CWH | CWGS, LLC
Ownership interest	34.10%	22.60%			34.10%		22.60%
Units held	30,227,061		30,227,061		30,227,061		18,935,916
Crestview Partners II GP LP | Tax receivable agreement
Liability under tax receivable agreement	$ 109,900		$ 109,900		$ 109,900		$ 19,200
Current portion of liabilities under tax receivable agreement	$ 7,400		7,400		$ 7,400		$ 1,000
Crestview Partners II GP LP | CWGS, LLC | Tax receivable agreement | IPO
Units issued in exchange		1,698,763
CW
Increase (decrease) in valuation allowance			$ (6,000)