Price-Risk Management Price-Risk Management (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) MMBTU bbl $ / MMBTU $ / Boe	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) MMBTU bbl $ / MMBTU $ / Boe	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) on Price Risk Derivatives, Net | $	$ (12,900)	$ 13,400	$ 66,900	$ 34,300
Cash Received (Paid) On Settlements of Derivative Contracts | $			76,150	$ 16,087
Cash Received (Paid) On Monetized Derivative Contracts | $			38,300
Receivables for Settled Derivatives | $	2,700		2,700		$ 2,900
Payables for Settled Derivatives | $	500		500		200
Derivative, Fair Value, Net | $	(300)		(300)		8,400
Other Current Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Fair Value, Gross Asset | $	11,800		11,800		12,800
Other Noncurrent Assets [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Fair Value, Gross Asset | $	2,300		2,300		3,900
Other Current Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Fair Value, Gross Liability | $	10,400		10,400		6,600
Other Noncurrent Liabilities [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Fair Value, Gross Liability | $	$ 4,000		$ 4,000		$ 1,600
Swap [Member] | Oil Derivative Swaps [Member] | Fourth Quarter 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	353,626		353,626
Derivative, Swap Type, Fixed Price | $ / Boe	47.72		47.72
Swap [Member] | Oil Derivative Swaps [Member] | First Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	215,538		215,538
Derivative, Swap Type, Fixed Price | $ / Boe	51.93		51.93
Swap [Member] | Oil Derivative Swaps [Member] | Second Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	195,646		195,646
Derivative, Swap Type, Fixed Price | $ / Boe	51.93		51.93
Swap [Member] | Oil Derivative Swaps [Member] | Third Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	179,759		179,759
Derivative, Swap Type, Fixed Price | $ / Boe	51.19		51.19
Swap [Member] | Oil Derivative Swaps [Member] | Fourth Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	163,812		163,812
Derivative, Swap Type, Fixed Price | $ / Boe	52.39		52.39
Swap [Member] | Oil Derivative Swaps [Member] | First Quarter 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	88,455		88,455
Derivative, Swap Type, Fixed Price | $ / Boe	36.79		36.79
Swap [Member] | Natural Gas Derivative Swaps [Member] | Fourth Quarter 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	7,817,000		7,817,000
Derivative, Swap Type, Fixed Price	2.63		2.63
Swap [Member] | Natural Gas Derivative Swaps [Member] | First Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	2,398,078		2,398,078
Derivative, Swap Type, Fixed Price	2.74		2.74
Swap [Member] | Natural Gas Derivative Swaps [Member] | Second Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	832,255		832,255
Derivative, Swap Type, Fixed Price	2.42		2.42
Swap [Member] | Natural Gas Derivative Swaps [Member] | Third Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	330,000		330,000
Derivative, Swap Type, Fixed Price	2.62		2.62
Swap [Member] | Natural Gas Derivative Swaps [Member] | Fourth Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	290,000		290,000
Derivative, Swap Type, Fixed Price	2.69		2.69
Collar Contracts [Member] | Oil Derivative Swaps [Member] | Fourth Quarter 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	115,000		115,000
Derivative, Average Floor Price	31.00		31.00
Derivative, Average Cap Price	36.15		36.15
Collar Contracts [Member] | Oil Derivative Swaps [Member] | First Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	155,475		155,475
Derivative, Average Floor Price	34.15		34.15
Derivative, Average Cap Price	39.24		39.24
Collar Contracts [Member] | Oil Derivative Swaps [Member] | Second Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	116,980		116,980
Derivative, Average Floor Price	34.33		34.33
Derivative, Average Cap Price	40.30		40.30
Collar Contracts [Member] | Oil Derivative Swaps [Member] | Third Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	90,620		90,620
Derivative, Average Floor Price	34.34		34.34
Derivative, Average Cap Price	39.87		39.87
Collar Contracts [Member] | Oil Derivative Swaps [Member] | Fourth Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	84,640		84,640
Derivative, Average Floor Price	34.70		34.70
Derivative, Average Cap Price	41.01		41.01
Collar Contracts [Member] | Oil Derivative Swaps [Member] | Second Quarter 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	86,450		86,450
Derivative, Average Floor Price	39.00		39.00
Derivative, Average Cap Price	46.50		46.50
Collar Contracts [Member] | Natural Gas Derivative Swaps [Member] | Fourth Quarter 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	920,000		920,000
Derivative, Average Floor Price	2.57		2.57
Derivative, Average Cap Price	2.93		2.93
Collar Contracts [Member] | Natural Gas Derivative Swaps [Member] | First Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	7,027,800		7,027,800
Derivative, Average Floor Price	2.53		2.53
Derivative, Average Cap Price	3.33		3.33
Collar Contracts [Member] | Natural Gas Derivative Swaps [Member] | Second Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	4,546,000		4,546,000
Derivative, Average Floor Price	2.18		2.18
Derivative, Average Cap Price	2.69		2.69
Collar Contracts [Member] | Natural Gas Derivative Swaps [Member] | Third Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	4,665,175		4,665,175
Derivative, Average Floor Price	2.02		2.02
Derivative, Average Cap Price	2.65		2.65
Collar Contracts [Member] | Natural Gas Derivative Swaps [Member] | Fourth Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	4,391,000		4,391,000
Derivative, Average Floor Price	2.25		2.25
Derivative, Average Cap Price	2.71		2.71
Collar Contracts [Member] | Natural Gas Derivative Swaps [Member] | First Quarter 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	4,415,000		4,415,000
Derivative, Average Floor Price	2.50		2.50
Derivative, Average Cap Price	3.35		3.35
Collar Contracts [Member] | Natural Gas Derivative Swaps [Member] | Second Quarter 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	4,200,000		4,200,000
Derivative, Average Floor Price	2.23		2.23
Derivative, Average Cap Price	2.70		2.70
Basis Swap [Member] | Natural Gas Basis Derivative Swaps [Member] | Fourth Quarter 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	11,868,000		11,868,000
Derivative, Swap Type, Fixed Price	(0.04)		(0.04)
Basis Swap [Member] | Natural Gas Basis Derivative Swaps [Member] | First Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	9,900,000		9,900,000
Derivative, Swap Type, Fixed Price	(0.02)		(0.02)
Basis Swap [Member] | Natural Gas Basis Derivative Swaps [Member] | Second Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	10,010,000		10,010,000
Derivative, Swap Type, Fixed Price	(0.02)		(0.02)
Basis Swap [Member] | Natural Gas Basis Derivative Swaps [Member] | Third Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	10,120,000		10,120,000
Derivative, Swap Type, Fixed Price	(0.02)		(0.02)
Basis Swap [Member] | Natural Gas Basis Derivative Swaps [Member] | Fourth Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | MMBTU	10,120,000		10,120,000
Derivative, Swap Type, Fixed Price	(0.02)		(0.02)
Basis Swap [Member] | Oil Basis Derivative [Member] | Fourth Quarter 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	465,275		465,275
Derivative, Swap Type, Fixed Price	1.20		1.20
Basis Swap [Member] | Oil Basis Derivative [Member] | First Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	373,750		373,750
Derivative, Swap Type, Fixed Price	1.19		1.19
Basis Swap [Member] | Oil Basis Derivative [Member] | Second Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	329,150		329,150
Derivative, Swap Type, Fixed Price	1.22		1.22
Basis Swap [Member] | Oil Basis Derivative [Member] | Third Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	262,200		262,200
Derivative, Swap Type, Fixed Price	1.27		1.27
Basis Swap [Member] | Oil Basis Derivative [Member] | Fourth Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	241,500		241,500
Derivative, Swap Type, Fixed Price	1.28		1.28
Basis Swap [Member] | Oil Basis Calendar Monthly Roll Differential Swap | Fourth Quarter 2020 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	469,900		469,900
Derivative, Swap Type, Fixed Price	(0.02)		(0.02)
Basis Swap [Member] | Oil Basis Calendar Monthly Roll Differential Swap | First Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	367,000		367,000
Derivative, Swap Type, Fixed Price	(0.40)		(0.40)
Basis Swap [Member] | Oil Basis Calendar Monthly Roll Differential Swap | Second Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	313,900		313,900
Derivative, Swap Type, Fixed Price	(0.37)		(0.37)
Basis Swap [Member] | Oil Basis Calendar Monthly Roll Differential Swap | Third Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	253,000		253,000
Derivative, Swap Type, Fixed Price	(0.34)		(0.34)
Basis Swap [Member] | Oil Basis Calendar Monthly Roll Differential Swap | Fourth Quarter 2021 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Oil and Gas Production Hedged Volumes | bbl	241,500		241,500
Derivative, Swap Type, Fixed Price	(0.33)		(0.33)