Industry Segment Information (Industry Segment Information) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019		Jun. 30, 2018		Jun. 30, 2019		Jun. 30, 2018
Revenues:
Revenues	$ 165,146		$ 203,303		$ 354,837		$ 408,435
Operating costs:
Operating costs	98,041		104,015		201,511		213,248
Depreciation, depletion, and amortization	66,292		58,373		128,418		115,439
Total expenses	164,333		162,388		329,929		328,687
General and administrative	10,064		8,712		19,805		19,474
(Gain) loss on disposition of assets	(422)		(161)		1,193		(322)
Income (loss) from operations	(8,829)		32,364		3,910		60,596
Gain (loss) on derivatives	7,927		(14,461)		995		(21,223)
Interest, net	(8,995)		(7,729)		(17,533)		(17,733)
Other	6		5		11		11
Income (loss) before income taxes	(9,891)		10,179		(12,617)		21,651
Oil and Natural Gas [Member]
Revenues:
Revenues	77,815	[1]	102,318	[2]	163,910	[3]	205,417	[4]
Operating costs:
Operating costs	37,519		33,682		71,527		70,834
Depreciation, depletion, and amortization	38,751		31,554		74,518		62,337
Total expenses	76,270		65,236		146,045		133,171
General and administrative	0		0		0		0
(Gain) loss on disposition of assets	(60)		(59)		(138)		(129)
Income (loss) from operations	1,605		37,141		18,003		72,375
Gain (loss) on derivatives	0		0		0		0
Interest, net	0		0		0		0
Other	0		0		0		0
Income (loss) before income taxes	1,605		37,141		18,003		72,375
Drilling [Member]
Revenues:
Revenues	50,773	[1]	52,767	[2]	108,972	[3]	103,477	[4]
Operating costs:
Operating costs	36,390		36,921		73,775		72,875
Depreciation, depletion, and amortization	13,504		13,726		26,203		27,038
Total expenses	49,894		50,647		99,978		99,913
General and administrative	0		0		0		0
(Gain) loss on disposition of assets	(296)		(57)		1,449		(84)
Income (loss) from operations	1,175		2,177		7,545		3,648
Gain (loss) on derivatives	0		0		0		0
Interest, net	0		0		0		0
Other	0		0		0		0
Income (loss) before income taxes	1,175		2,177		7,545		3,648
Mid-Stream [Member]
Revenues:
Revenues	54,630	[1]	75,406	[2]	125,139	[3]	150,056	[4]
Operating costs:
Operating costs	41,550		59,786		97,679		118,806
Depreciation, depletion, and amortization	12,102		11,175		23,828		22,228
Total expenses	53,652		70,961		121,507		141,034
General and administrative	0		0		0		0
(Gain) loss on disposition of assets	(66)		(45)		(108)		(79)
Income (loss) from operations	1,044		4,490		3,740		9,101
Gain (loss) on derivatives	0		0		0		0
Interest, net	(345)		(304)		(681)		(453)
Other	0		0		0		0
Income (loss) before income taxes	699		4,186		3,059		8,648
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		1,918		3,869		3,836
Total expenses	1,935		1,918		3,869		3,836
General and administrative	10,064		8,712		19,805		19,474
(Gain) loss on disposition of assets	0		0		(10)		(30)
Income (loss) from operations	(11,999)		(10,630)		(23,664)		(23,280)
Gain (loss) on derivatives	7,927		(14,461)		995		(21,223)
Interest, net	(8,650)		(7,425)		(16,852)		(17,280)
Other	6		5		11		11
Income (loss) before income taxes	(12,716)		(32,511)		(39,510)		(61,772)
Eliminations [Member]
Revenues:
Revenues	(18,072)	[1]	(27,188)	[2]	(43,184)	[3]	(50,515)	[4]
Operating costs:
Operating costs	(17,418)		(26,374)		(41,470)		(49,267)
Depreciation, depletion, and amortization	0		0		0		0
Total expenses	(17,418)		(26,374)		(41,470)		(49,267)
General and administrative	0		0		0		0
(Gain) loss on disposition of assets	0		0		0		0
Income (loss) from operations	(654)		(814)		(1,714)		(1,248)
Gain (loss) on derivatives	0		0		0		0
Interest, net	0		0		0		0
Other	0		0		0		0
Income (loss) before income taxes	(654)		(814)		(1,714)		(1,248)
Oil and natural gas
Revenues:
Revenues	77,815		102,318		163,910		205,417
Operating costs:
Operating costs	36,242		32,418		68,956		68,380
Oil and natural gas | Oil and Natural Gas [Member]
Revenues:
Revenues	77,815	[1]	102,318	[2]	163,910	[3]	205,417	[4]
Operating costs:
Operating costs	37,519		33,682		71,527		70,834
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	(1,277)		(1,264)		(2,571)		(2,454)
Contract drilling
Revenues:
Revenues	43,037		46,926		94,192		92,915
Operating costs:
Operating costs	29,308		31,894		60,709		63,561
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	50,773	[1]	52,767	[2]	108,972	[3]	103,477	[4]
Operating costs:
Operating costs	36,390		36,921		73,775		72,875
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	(7,736)	[1]	(5,841)	[2]	(14,780)	[3]	(10,562)	[4]
Operating costs:
Operating costs	(7,082)		(5,027)		(13,066)		(9,314)
Gas gathering and processing
Revenues:
Revenues	44,294		54,059		96,735		110,103
Operating costs:
Operating costs	32,491		39,703		71,846		81,307
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	54,630	[1]	75,406	[2]	125,139	[3]	150,056	[4]
Operating costs:
Operating costs	41,550		59,786		97,679		118,806
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	(10,336)	[1]	(21,347)	[2]	(28,404)	[3]	(39,953)	[4]
Operating costs:
Operating costs	$ (9,059)		$ (20,083)		$ (25,833)		$ (37,499)

[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.