Industry Segments - Corporate Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
General and administrative expense	$ 25,256	$ 34,926	$ 89,807	$ 105,498
Depreciation, amortization, and accretion	29,604	30,867	88,906	93,312
Interest expense, net	17,631	18,146	53,073	55,054
Warrants fair value adjustment			(326)	(1,035)
Other (income) expense, net	(2,137)	(690)	2,141	(1,014)
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	21,425	9,079	68,786	35,954
Corporate Overhead [Member]
Segment Reporting Information [Line Items]
General and administrative expense	8,959	12,573	28,650	39,012
Depreciation, amortization, and accretion	270	167	643	507
Interest expense, net	4,706	5,495	14,909	16,533
Warrants fair value adjustment	0	78	(327)	(1,035)
Other (income) expense, net	(463)	(382)	(50)	(96)
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ 13,472	$ 17,931	$ 43,825	$ 54,921