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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
RELATED PARTY TRANSACTIONS
Sales to related parties	$ 0.2	$ 3.6	$ 2.6	$ 9.9
Purchases from related party vendors	$ 1.5	6.4	$ 5.7	12.4
Minimum
RELATED PARTY TRANSACTIONS
Beneficial ownership (as a percent)	5.00%		5.00%
Tax Receivable Agreement \| Legacy Owner Holdco and Crestview GP
RELATED PARTY TRANSACTIONS
Percentage of net tax savings for payment to TRA Holders			85.00%
Tax Receivable Agreement \| Contributing Legacy Owners
RELATED PARTY TRANSACTIONS
Percentage of net tax savings for payment to TRA Holders			85.00%
Property and equipment
RELATED PARTY TRANSACTIONS
Purchases from related party vendors	$ 0.1	0.4	$ 0.3	1.9
Inventory and consumables
RELATED PARTY TRANSACTIONS
Purchases from related party vendors			0.1
Rent of certain equipment or other services
RELATED PARTY TRANSACTIONS
Purchases from related party vendors	$ 1.4	5.6	5.1	9.5
Management, consulting and other services
RELATED PARTY TRANSACTIONS
Purchases from related party vendors		$ 0.4	$ 0.2	$ 1.0