Significant Concentrations (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		8 Months Ended	9 Months Ended
	Feb. 08, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2019	Dec. 31, 2018
Concentration Risk [Line Items]
Total revenue		$ 119,058	$ 139,804	$ 263,022	$ 378,310
AEM
Concentration Risk [Line Items]
Total revenue		7,643	114,109	234,850	117,003
Fees paid		56	216	499	467
Total fees paid to ARM		328	216	499	1,950
Accounts receivable		5,400			5,400	$ 43,800
Marketing fees | AEM
Concentration Risk [Line Items]
Fees paid		$ 272	$ 0	$ 0	$ 1,483
Predecessor
Concentration Risk [Line Items]
Total revenue	$ 47,639
Predecessor | AEM
Concentration Risk [Line Items]
Total revenue	28,757
Fees paid	66
Total fees paid to ARM	66
Predecessor | Marketing fees | AEM
Concentration Risk [Line Items]
Fees paid	$ 0