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Significant Concentrations (Details) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended							11 Months Ended	12 Months Ended
	Feb. 08, 2018	Mar. 31, 2018	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Concentration Risk [Line Items]
Sales										$ 414,507
Revenues		$ 34,090	$ 185,589	$ 122,873	$ 66,459	$ 46,567	$ 57,923	$ 79,800	$ 95,079	409,011
ARM
Concentration Risk [Line Items]
Amount paid for marketing fees	$ 100									800		$ 800	$ 1,900
Accounts receivable			$ 38,400							38,400	$ 38,400
Sales										309,700		199,200	114,800
Predecessor
Concentration Risk [Line Items]
Sales	40,136											269,386	142,356
Revenues	47,639											279,369	$ 101,899
Predecessor \| ARM
Concentration Risk [Line Items]
Accounts receivable						$ 22,400						$ 22,400
Sales	$ 28,800
ARM \| AM Contributor
Concentration Risk [Line Items]
Concentration risk percentage											10.00%
Marketing fees
Concentration Risk [Line Items]
Amount paid for marketing fees										$ 1,400