Condensed Consolidating Financial Information - Summary of Condensed Consolidating Financial Position (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 106,952	$ 87,022
Accounts receivable
Trade, net	81,027	107,842
Joint interest, net	32,894	16,552
Other	36,556	6,346
Assets from price risk management activities	192,553	8,393
Prepaid assets	50,273	65,877
Other current assets	2,046	1,952
Total current assets	502,301	293,984
Property and equipment:
Proved properties	4,538,100	4,066,260
Unproved properties, not subject to amortization	277,050	194,532
Other property and equipment	31,966	29,843
Total property and equipment	4,847,116	4,290,635
Accumulated depreciation, depletion and amortization	(2,158,566)	(2,065,023)
Total property and equipment, net	2,688,550	2,225,612
Other long-term assets:
Assets from price risk management activities	8,794
Other well equipment inventory	9,178	7,732
Operating lease assets	7,590	7,779
Other assets	21,774	54,375
Total assets	3,238,187	2,589,482
Current liabilities:
Accounts payable	58,750	71,357
Accrued liabilities	138,271	154,816
Accrued royalties	24,631	31,729
Current portion of asset retirement obligations	38,028	61,051
Liabilities from price risk management activities	4,286	19,476
Accrued interest payable	22,257	10,249
Current portion of operating lease liabilities	1,613	1,594
Other current liabilities	20,918	20,180
Total current liabilities	308,754	370,452
Long-term liabilities:
Long-term debt, net of discount and deferred financing costs	1,033,162	732,981
Asset retirement obligations	387,868	308,427
Liabilities from price risk management activities	1,898	511
Operating lease liabilities	19,138	17,239
Other long-term liabilities	92,470	81,595
Total liabilities	1,843,290	1,511,205
Commitments and Contingencies
Stockholders' equity	1,394,897	1,078,277	$ 899,986	$ 1,007,496
Total liabilities and stockholders' equity	3,238,187	2,589,482
Parent
Accounts receivable
Other current assets	53
Total current assets	53
Other long-term assets:
Investments in subsidiaries	1,417,909	1,045,886
Other assets	1	33,371
Total assets	1,417,963	1,079,257
Current liabilities:
Accounts payable	564	428
Other current liabilities	255	255
Total current liabilities	819	683
Long-term liabilities:
Other long-term liabilities	22,247	297
Total liabilities	23,066	980
Commitments and Contingencies
Stockholders' equity	1,394,897	1,078,277
Total liabilities and stockholders' equity	1,417,963	1,079,257
Subsidiary Issuer
Current assets:
Cash and cash equivalents	88,453	78,780
Accounts receivable
Other	28,153	474
Assets from price risk management activities	192,553	8,393
Prepaid assets	2,809	33,323
Total current assets	311,968	120,970
Property and equipment:
Other property and equipment	24,920	23,142
Total property and equipment	24,920	23,142
Accumulated depreciation, depletion and amortization	(11,728)	(11,001)
Total property and equipment, net	13,192	12,141
Other long-term assets:
Assets from price risk management activities	8,794
Operating lease assets	3,314	3,178
Investments in subsidiaries	2,167,746	1,690,362
Other assets	364	364
Total assets	2,505,378	1,827,015
Current liabilities:
Accounts payable	5,151	5,145
Accrued liabilities	10,501	4,740
Liabilities from price risk management activities	4,286	19,476
Accrued interest payable	22,105	10,211
Current portion of operating lease liabilities	378	196
Total current liabilities	42,421	39,768
Long-term liabilities:
Long-term debt, net of discount and deferred financing costs	1,027,102	726,921
Liabilities from price risk management activities	1,898	511
Operating lease liabilities	16,048	13,929
Total liabilities	1,087,469	781,129
Commitments and Contingencies
Stockholders' equity	1,417,909	1,045,886
Total liabilities and stockholders' equity	2,505,378	1,827,015
Guarantors
Current assets:
Cash and cash equivalents	5,231	593
Accounts receivable
Trade, net	81,027	107,842
Joint interest, net	26,906	11,567
Other	8,097	5,555
Prepaid assets	47,442	32,529
Other current assets	1,993	1,952
Total current assets	170,696	160,038
Property and equipment:
Proved properties	4,538,100	4,066,260
Unproved properties, not subject to amortization	166,450	87,618
Other property and equipment	6,829	6,484
Total property and equipment	4,711,379	4,160,362
Accumulated depreciation, depletion and amortization	(2,146,773)	(2,053,971)
Total property and equipment, net	2,564,606	2,106,391
Other long-term assets:
Other well equipment inventory	9,178	7,732
Operating lease assets	3,030	3,224
Other assets	2,396	2,136
Total assets	2,749,906	2,279,521
Current liabilities:
Accounts payable	50,073	58,827
Accrued liabilities	117,001	145,051
Accrued royalties	24,631	31,729
Current portion of asset retirement obligations	38,028	61,051
Accrued interest payable	152	38
Current portion of operating lease liabilities	773	821
Other current liabilities	20,663	19,925
Total current liabilities	251,321	317,442
Long-term liabilities:
Long-term debt, net of discount and deferred financing costs	6,060	6,060
Asset retirement obligations	387,868	308,427
Operating lease liabilities	2,268	2,416
Other long-term liabilities	70,223	81,298
Total liabilities	717,740	715,643
Commitments and Contingencies
Stockholders' equity	2,032,166	1,563,878
Total liabilities and stockholders' equity	2,749,906	2,279,521
Non-Guarantors
Current assets:
Cash and cash equivalents	13,268	7,649
Accounts receivable
Joint interest, net	5,988	4,985
Other	306	317
Prepaid assets	22	25
Total current assets	19,584	12,976
Property and equipment:
Unproved properties, not subject to amortization	110,600	106,914
Other property and equipment	217	217
Total property and equipment	110,817	107,131
Accumulated depreciation, depletion and amortization	(65)	(51)
Total property and equipment, net	110,752	107,080
Other long-term assets:
Operating lease assets	1,246	1,377
Other assets	19,013	18,504
Total assets	150,595	139,937
Current liabilities:
Accounts payable	2,962	6,957
Accrued liabilities	10,769	5,025
Current portion of operating lease liabilities	462	577
Total current liabilities	14,193	12,559
Long-term liabilities:
Operating lease liabilities	822	894
Total liabilities	15,015	13,453
Commitments and Contingencies
Stockholders' equity	135,580	126,484
Total liabilities and stockholders' equity	150,595	139,937
Elimination
Other long-term assets:
Investments in subsidiaries	(3,585,655)	(2,736,248)
Total assets	(3,585,655)	(2,736,248)
Long-term liabilities:
Commitments and Contingencies
Stockholders' equity	(3,585,655)	(2,736,248)
Total liabilities and stockholders' equity	$ (3,585,655)	$ (2,736,248)