Supplemental Guarantor Financial Information - I/S (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Condensed Consolidated Statements of Comprehensive (Loss) Income
Revenues	$ 306,602	$ 318,270	$ 1,349,405
Operating costs and expenses	289,933
Loss on disposal and impairment of assets	921	968
Income from operations	15,748	10,174	86,434
Interest expense, net, including amortization of deferred financing costs and note discount	9,907
Equity in earnings of subsidiaries	0
Other expenses (income)	3,829	(7,207)
Income before income taxes	2,012	7,446
Income tax (benefit) expense	(3,737)	3,129
Net income	5,749	4,317	48,265
Net loss attributable to noncontrolling interests	(6)	(2)
Net income attributable to controlling interests and available to common shareholders	5,755	4,319	48,274
Other comprehensive (loss) income attributable to controlling interest	(59,503)
Comprehensive (loss) income attributable to controlling interests	(53,748)	$ (3,284)
Eliminations
Condensed Consolidated Statements of Comprehensive (Loss) Income
Revenues	(17,469)		(72,531)
Operating costs and expenses	(17,909)
Income from operations	440		300
Interest expense, net, including amortization of deferred financing costs and note discount	62
Equity in earnings of subsidiaries	27,215
Other expenses (income)	(7,600)
Income before income taxes	(19,237)
Income tax (benefit) expense	0
Net income	(19,237)		(111,534)
Net loss attributable to noncontrolling interests	(6)
Net income attributable to controlling interests and available to common shareholders	(19,231)		(111,525)
Other comprehensive (loss) income attributable to controlling interest	64,956
Comprehensive (loss) income attributable to controlling interests	45,725
Parent | Reportable Legal Entities
Condensed Consolidated Statements of Comprehensive (Loss) Income
Revenues	0		0
Operating costs and expenses	5,797
Income from operations	(5,797)		(35,637)
Interest expense, net, including amortization of deferred financing costs and note discount	0
Equity in earnings of subsidiaries	(12,653)
Other expenses (income)	2,728
Income before income taxes	4,128
Income tax (benefit) expense	(1,621)
Net income	5,749		48,265
Net loss attributable to noncontrolling interests	0
Net income attributable to controlling interests and available to common shareholders	5,749		48,265
Other comprehensive (loss) income attributable to controlling interest	(59,503)
Comprehensive (loss) income attributable to controlling interests	(53,754)
Issuer | Reportable Legal Entities
Condensed Consolidated Statements of Comprehensive (Loss) Income
Revenues	161,390		668,527
Operating costs and expenses	154,918
Loss on disposal and impairment of assets	417
Income from operations	6,055		40,733
Interest expense, net, including amortization of deferred financing costs and note discount	8,602
Equity in earnings of subsidiaries	(17,589)
Other expenses (income)	7,696
Income before income taxes	7,346
Income tax (benefit) expense	(2,289)
Net income	9,635		20,546
Net loss attributable to noncontrolling interests	0
Net income attributable to controlling interests and available to common shareholders	9,635		20,546
Other comprehensive (loss) income attributable to controlling interest	(32,506)
Comprehensive (loss) income attributable to controlling interests	(22,871)
Guarantors | Reportable Legal Entities
Condensed Consolidated Statements of Comprehensive (Loss) Income
Revenues	78,136		351,330
Operating costs and expenses	61,126
Loss on disposal and impairment of assets	104
Income from operations	16,906		70,835
Interest expense, net, including amortization of deferred financing costs and note discount	1,201
Equity in earnings of subsidiaries	2,786
Other expenses (income)	6,543
Income before income taxes	6,376
Income tax (benefit) expense	(415)
Net income	6,791		63,952
Net loss attributable to noncontrolling interests	0
Net income attributable to controlling interests and available to common shareholders	6,791		63,952
Other comprehensive (loss) income attributable to controlling interest	4,287
Comprehensive (loss) income attributable to controlling interests	11,078
Non-Guarantors | Reportable Legal Entities
Condensed Consolidated Statements of Comprehensive (Loss) Income
Revenues	84,545		402,079
Operating costs and expenses	86,001
Loss on disposal and impairment of assets	400
Income from operations	(1,856)		10,203
Interest expense, net, including amortization of deferred financing costs and note discount	42
Equity in earnings of subsidiaries	241
Other expenses (income)	(5,538)
Income before income taxes	3,399
Income tax (benefit) expense	588
Net income	2,811		27,036
Net loss attributable to noncontrolling interests	0
Net income attributable to controlling interests and available to common shareholders	2,811		$ 27,036
Other comprehensive (loss) income attributable to controlling interest	(36,737)
Comprehensive (loss) income attributable to controlling interests	$ (33,926)