Industry Segment Information (Industry Segment Information) (Details) - USD ($) $ in Thousands	3 Months Ended					9 Months Ended
	Sep. 30, 2019		Dec. 31, 2018	Sep. 30, 2018		Sep. 30, 2019		Sep. 30, 2018
Revenues:
Revenues	$ 155,439			$ 220,058		$ 510,276		$ 628,493
Operating costs:
Operating costs	92,653			107,305		294,164		320,553
Depreciation, depletion, and amortization	70,214			63,537		198,632		178,976
Impairments	234,880			0		234,880		0
Total expenses	397,747			170,842		727,676		499,529
General and administrative	10,094			9,278		29,899		28,752
(Gain) loss on disposition of assets	231			(253)		1,424		(575)
Income (loss) from operations	(252,633)			40,191		(248,723)		100,787
Gain (loss) on derivatives	4,237			(4,385)		5,232		(25,608)
Interest, net	(9,534)			(7,945)		(27,067)		(25,678)
Other	(622)			6		(611)		17
Income (loss) before income taxes	(258,552)			27,867		(271,169)		49,518
Oil and Natural Gas [Member]
Revenues:
Revenues	78,045	[1]		111,623	[2]	241,955	[3]	317,040	[4]
Operating costs:
Operating costs	36,621			33,400		108,148		104,234
Depreciation, depletion, and amortization	43,587			35,460		118,105		97,797
Impairments	169,806					169,806
Total expenses	250,014			68,860		396,059		202,031
General and administrative	0			0		0		0
(Gain) loss on disposition of assets	(28)			(7)		(166)		(136)
Income (loss) from operations	(171,941)			42,770		(153,938)		115,145
Gain (loss) on derivatives	0			0		0		0
Interest, net	0			0		0		0
Other	0			0		0		0
Income (loss) before income taxes	(171,941)			42,770		(153,938)		115,145
Drilling [Member]
Revenues:
Revenues	38,626	[1]		58,012	[2]	147,598	[3]	161,489	[4]
Operating costs:
Operating costs	29,913			38,246		103,688		111,121
Depreciation, depletion, and amortization	12,845			14,889		39,048		41,927
Impairments	62,809		$ 147,900			62,809
Total expenses	105,567			53,135		205,545		153,048
General and administrative	0			0		0		0
(Gain) loss on disposition of assets	288			(230)		1,737		(314)
Income (loss) from operations	(67,229)			5,107		(59,684)		8,755
Gain (loss) on derivatives	0			0		0		0
Interest, net	0			0		0		0
Other	(627)			0		(627)		0
Income (loss) before income taxes	(67,856)			5,107		(60,311)		8,755
Mid-Stream [Member]
Revenues:
Revenues	48,585	[1]		82,882	[2]	173,724	[3]	232,938	[4]
Operating costs:
Operating costs	36,023			66,932		133,702		185,738
Depreciation, depletion, and amortization	11,847			11,265		35,675		33,493
Impairments	2,265					2,265
Total expenses	50,135			78,197		171,642		219,231
General and administrative	0			0		0		0
(Gain) loss on disposition of assets	(28)			(16)		(136)		(95)
Income (loss) from operations	(1,522)			4,701		2,218		13,802
Gain (loss) on derivatives	0			0		0		0
Interest, net	(448)			(381)		(1,129)		(834)
Other	0			0		0		0
Income (loss) before income taxes	(1,970)			4,320		1,089		12,968
Corporate and Other [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Depreciation, depletion, and amortization	1,935			1,923		5,804		5,759
Impairments	0					0
Total expenses	1,935			1,923		5,804		5,759
General and administrative	10,094			9,278		29,899		28,752
(Gain) loss on disposition of assets	(1)			0		(11)		(30)
Income (loss) from operations	(12,028)			(11,201)		(35,692)		(34,481)
Gain (loss) on derivatives	4,237			(4,385)		5,232		(25,608)
Interest, net	(9,086)			(7,564)		(25,938)		(24,844)
Other	5			6		16		17
Income (loss) before income taxes	(16,872)			(23,144)		(56,382)		(84,916)
Eliminations [Member]
Revenues:
Revenues	(9,817)	[1]		(32,459)	[2]	(53,001)	[3]	(82,974)	[4]
Operating costs:
Operating costs	(9,904)			(31,273)		(51,374)		(80,540)
Depreciation, depletion, and amortization	0			0		0		0
Impairments	0					0
Total expenses	(9,904)			(31,273)		(51,374)		(80,540)
General and administrative	0			0		0		0
(Gain) loss on disposition of assets	0			0		0		0
Income (loss) from operations	87			(1,186)		(1,627)		(2,434)
Gain (loss) on derivatives	0			0		0		0
Interest, net	0			0		0		0
Other	0			0		0		0
Income (loss) before income taxes	87			(1,186)		(1,627)		(2,434)
Oil and natural gas
Revenues:
Revenues	78,045			111,623		241,955		317,040
Operating costs:
Operating costs	35,364			32,139		104,320		100,519
Oil and natural gas | Oil and Natural Gas [Member]
Revenues:
Revenues	78,045	[1]		111,623	[2]	241,955	[3]	317,040	[4]
Operating costs:
Operating costs	36,621			33,400		108,148		104,234
Oil and natural gas | Drilling [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Oil and natural gas | Mid-Stream [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Oil and natural gas | Corporate and Other [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Oil and natural gas | Eliminations [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	(1,257)			(1,261)		(3,828)		(3,715)
Contract drilling
Revenues:
Revenues	37,596			50,612		131,788		143,527
Operating costs:
Operating costs	28,796			32,032		89,505		95,593
Contract drilling | Oil and Natural Gas [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Contract drilling | Drilling [Member]
Revenues:
Revenues	38,626	[1]		58,012	[2]	147,598	[3]	161,489	[4]
Operating costs:
Operating costs	29,913			38,246		103,688		111,121
Contract drilling | Mid-Stream [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Contract drilling | Corporate and Other [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Contract drilling | Eliminations [Member]
Revenues:
Revenues	(1,030)	[1]		(7,400)	[2]	(15,810)	[3]	(17,962)	[4]
Operating costs:
Operating costs	(1,117)			(6,214)		(14,183)		(15,528)
Gas gathering and processing
Revenues:
Revenues	39,798			57,823		136,533		167,926
Operating costs:
Operating costs	28,493			43,134		100,339		124,441
Gas gathering and processing | Oil and Natural Gas [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Gas gathering and processing | Drilling [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Gas gathering and processing | Mid-Stream [Member]
Revenues:
Revenues	48,585	[1]		82,882	[2]	173,724	[3]	232,938	[4]
Operating costs:
Operating costs	36,023			66,932		133,702		185,738
Gas gathering and processing | Corporate and Other [Member]
Revenues:
Revenues	0	[1]		0	[2]	0	[3]	0	[4]
Operating costs:
Operating costs	0			0		0		0
Gas gathering and processing | Eliminations [Member]
Revenues:
Revenues	(8,787)	[1]		(25,059)	[2]	(37,191)	[3]	(65,012)	[4]
Operating costs:
Operating costs	$ (7,530)			$ (23,798)		$ (33,363)		$ (61,297)

[1] The revenues for oil and natural gas occur at a point in time. The revenues for contract drilling and gas gathering and processing occur over time.

[2] The revenues for oil and natural gas occur at a point in time. The revenues for contract drilling and gas gathering and processing occur over time.

[3] The revenues for oil and natural gas occur at a point in time. The revenues for contract drilling and gas gathering and processing occur over time.

[4] The revenues for oil and natural gas occur at a point in time. The revenues for contract drilling and gas gathering and processing occur over time.