CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 2,817	$ 6,060
Accounts receivable—oil and natural gas sales	65,645	121,210
Accounts receivable—joint interest and other	19,389	47,975
Prepaid expenses and other current assets	10,862	4,431
Short-term derivative instruments	53,188	126,201
Total current assets	151,901	305,877
Property and equipment:
Oil and natural gas properties, full-cost accounting, $1,564,189 and $1,686,666 excluded from amortization in 2020 and 2019, respectively	10,730,992	10,595,735
Other property and equipment	96,838	96,719
Accumulated depletion, depreciation, amortization and impairment	(8,457,464)	(7,228,660)
Property and equipment, net	2,370,366	3,463,794
Other assets:
Equity investments	13,052	32,044
Long-term derivative instruments	4,298	563
Deferred tax asset	0	7,563
Operating lease assets	3,640	14,168
Operating lease assets—related parties	0	43,270
Other assets	37,000	15,540
Total other assets	57,990	113,148
Total assets	2,580,257	3,882,819
Current liabilities:
Accounts payable and accrued liabilities	315,575	415,218
Short-term derivative instruments	8,540	303
Current portion of operating lease liabilities	3,356	13,826
Current portion of operating lease liabilities—related parties	0	21,220
Current maturities of long-term debt	649	631
Total current liabilities	328,120	451,198
Long-term derivative instruments	45,615	53,135
Asset retirement obligation	61,371	60,355
Uncertain tax position liability	3,209	3,127
Non-current operating lease liabilities	284	342
Non-current operating lease liabilities—related parties	0	22,050
Long-term debt, net of current maturities	1,910,318	1,978,020
Total liabilities	2,348,917	2,568,227
Commitments and contingencies (Note 9)
Preferred stock, $0.01 par value; 5.0 million shares authorized (30 thousand authorized as redeemable 12% cumulative preferred stock, Series A), and none issued and outstanding	0	0
Stockholders’ equity:
Common stock - $0.01 par value, 200.0 million shares authorized, 160.1 million issued and outstanding at June 30, 2020 and 159.7 million at December 31, 2019	1,601	1,597
Paid-in capital	4,211,062	4,207,554
Accumulated other comprehensive loss	(54,991)	(46,833)
Accumulated deficit	(3,926,332)	(2,847,726)
Total stockholders’ equity	231,340	1,314,592
Total liabilities and stockholders’ equity	$ 2,580,257	$ 3,882,819