Guarantor/Non Guarantor Condensed Consolidating Financial Statements (Statements of Operations) (Details) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended			5 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2020	May 31, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	May 31, 2020	Jun. 30, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 11,163	$ 28,048		$ 152,843		$ 142,370	$ 299,411
Costs and expenses:
Operating costs	8,743	22,025		115,970		114,047	224,555
Depreciation and amortization	5,236	13,663		22,851		35,647	45,504
General and administrative	4,213	7,392		18,028		22,047	37,786
Pre-petition restructuring charges	0	(252)		0		16,822	0
Intercompany leasing	0	0		0		0	0
Impairment	388	0		332		17,853	1,378
Bad debt expense (recovery), net	(283)	482		(348)		1,209	(286)
Gain (loss) on dispositions of property and equipment, net	(460)	(272)		(1,126)		(989)	(2,201)
Total costs and expenses	17,837	43,038		155,707		206,636	306,736
Income (loss) from operations	(6,674)	(14,990)		(2,864)		(64,266)	(7,325)
Other income (expense):
Equity in earnings of subsidiaries	0	0		0		0	0
Interest expense, net of interest capitalized	(2,215)	(4,135)		(10,105)		(12,294)	(19,990)
Loss on extinguishment of debt	0	3,723				4,215	0	$ 0
Reorganization Items, net	(1,144)	(15,240)		0		(21,903)	0
Other income, net	(230)	2,212		349		(3,333)	1,033
Total other income (expense), net	(3,589)	(20,886)		(9,756)		(41,745)	(18,957)
Income (loss) before income taxes	(10,263)	(35,876)		(12,620)		(106,011)	(26,282)
Income tax (expense) benefit	446	755		(324)		1,786	(1,777)
Net loss	(9,817)	(35,121)	$ (69,104)	(12,944)	$ (15,115)	(104,225)	(28,059)
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0		0		0	0
Costs and expenses:
Operating costs	0	0		0		0	0
Depreciation and amortization	0	0		0		0	0
General and administrative	(65)	(90)		(135)		(225)	(270)
Pre-petition restructuring charges		0				0
Intercompany leasing	0	0		0		0	0
Impairment	0			0		0	0
Bad debt expense (recovery), net	0	0		0		0	0
Gain (loss) on dispositions of property and equipment, net	0	0		0		0	0
Total costs and expenses	(65)	(90)		(135)		(225)	(270)
Income (loss) from operations	65	90		135		225	270
Other income (expense):
Equity in earnings of subsidiaries	5,968	204,365		(6,736)		236,091	(11,968)
Interest expense, net of interest capitalized	0	0		0		0	0
Loss on extinguishment of debt		0				0
Reorganization Items, net	0	0				0
Other income, net	(65)	(90)		(135)		(225)	(270)
Total other income (expense), net	5,903	204,275		(6,871)		235,866	(12,238)
Income (loss) before income taxes	5,968	204,365		(6,736)		236,091	(11,968)
Income tax (expense) benefit	0	0		0		0	0
Net loss	5,968	204,365		(6,736)		236,091	(11,968)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	10,335	26,575		127,421		126,442	252,346
Costs and expenses:
Operating costs	7,680	20,487		97,417		100,372	189,519
Depreciation and amortization	4,036	12,673		21,268		33,129	42,298
General and administrative	1,703	4,277		10,579		12,489	22,025
Pre-petition restructuring charges		0				0
Intercompany leasing	(405)	(810)		(1,215)		(2,025)	(2,430)
Impairment	388			332		17,853	1,378
Bad debt expense (recovery), net	(283)	482		(348)		1,209	(286)
Gain (loss) on dispositions of property and equipment, net	(460)	(272)		(1,121)		(992)	(2,105)
Total costs and expenses	12,659	36,837		126,912		162,035	250,399
Income (loss) from operations	(2,324)	(10,262)		509		(35,593)	1,947
Other income (expense):
Equity in earnings of subsidiaries	(1,656)	(2,086)		3,431		(8,594)	5,895
Interest expense, net of interest capitalized	0	(1)		(1)		0	(15)
Loss on extinguishment of debt		0				0
Reorganization Items, net	(403)	(231,420)				(231,420)
Other income, net	89	160		401		394	667
Total other income (expense), net	(1,970)	(233,347)		3,831		(239,620)	6,547
Income (loss) before income taxes	(4,294)	(243,609)		4,340		(275,213)	8,494
Income tax (expense) benefit	(18)	41,330		(1,035)		47,716	(2,421)
Net loss	(4,312)	(202,279)		3,305		(227,497)	6,073
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	828	1,473		25,422		15,928	47,065
Costs and expenses:
Operating costs	1,063	1,538		18,553		13,675	35,036
Depreciation and amortization	1,076	843		1,373		2,144	2,716
General and administrative	146	283		677		918	1,128
Pre-petition restructuring charges		0				0
Intercompany leasing	405	810		1,215		2,025	2,430
Impairment	0			0		0	0
Bad debt expense (recovery), net	0	0		0		0	0
Gain (loss) on dispositions of property and equipment, net	0	0		(5)		0	(96)
Total costs and expenses	2,690	3,474		21,813		18,762	41,214
Income (loss) from operations	(1,862)	(2,001)		3,609		(2,834)	5,851
Other income (expense):
Equity in earnings of subsidiaries	0	0		0		0	0
Interest expense, net of interest capitalized	2	4		(45)		21	(42)
Loss on extinguishment of debt		0				0
Reorganization Items, net	0	(829)				(829)
Other income, net	(260)	2,109		(8)		(3,498)	339
Total other income (expense), net	(258)	1,284		(53)		(4,306)	297
Income (loss) before income taxes	(2,120)	(717)		3,556		(7,140)	6,148
Income tax (expense) benefit	464	(1,369)		(125)		(1,454)	(253)
Net loss	(1,656)	(2,086)		3,431		(8,594)	5,895
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0		0		0	0
Costs and expenses:
Operating costs	0	0		0		0	0
Depreciation and amortization	124	147		210		374	490
General and administrative	2,429	2,922		6,907		8,865	14,903
Pre-petition restructuring charges		(252)				16,822
Intercompany leasing	0	0		0		0	0
Impairment	0			0		0	0
Bad debt expense (recovery), net	0	0		0		0	0
Gain (loss) on dispositions of property and equipment, net	0	0		0		3	0
Total costs and expenses	2,553	2,817		7,117		26,064	15,393
Income (loss) from operations	(2,553)	(2,817)		(7,117)		(26,064)	(15,393)
Other income (expense):
Equity in earnings of subsidiaries	(4,312)	(202,279)		3,305		(227,497)	6,073
Interest expense, net of interest capitalized	(2,217)	(4,138)		(10,059)		(12,315)	(19,933)
Loss on extinguishment of debt		3,723				4,215
Reorganization Items, net	(741)	217,009				210,346
Other income, net	6	33		91		(4)	297
Total other income (expense), net	(7,264)	6,902		(6,663)		(33,685)	(13,563)
Income (loss) before income taxes	(9,817)	4,085		(13,780)		(59,749)	(28,956)
Income tax (expense) benefit	0	(39,206)		836		(44,476)	897
Net loss	$ (9,817)	$ (35,121)		$ (12,944)		$ (104,225)	$ (28,059)