Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets
Cash	$ 40,024	$ 64,545
Restricted cash	25,104	19,439
Accounts receivable
Oil and natural gas revenues	95,228	68,161
Joint interest billings	67,546	61,831
Other	26,639	16,159
Derivative instruments	0	49,929
Lease and well equipment inventory	10,744	17,564
Prepaid expenses and other current assets	13,207	8,057
Total current assets	278,492	305,685
Oil and natural gas properties, full-cost method
Evaluated	4,557,265	3,780,236
Unproved and unevaluated	1,126,992	1,199,511
Midstream properties	643,903	428,025
Midstream properties	27,021	22,041
Less accumulated depletion, depreciation and amortization	(2,655,586)	(2,306,949)
Net property and equipment	3,699,595	3,122,864
Other assets
Deferred income taxes	0	20,457
Other long-term assets	91,589	6,512
Total other assets	91,589	26,969
Total assets	4,069,676	3,455,518
Current liabilities
Accounts payable	25,230	66,970
Accrued liabilities	200,695	170,855
Royalties payable	85,193	64,776
Amounts due to affiliates	19,606	13,052
Derivative instruments	1,897	0
Advances from joint interest owners	14,837	10,968
Amounts due to joint ventures	486	2,373
Other current liabilities	51,828	1,028
Total current liabilities	399,772	330,022
Long-term liabilities
Borrowings under Credit Agreement	255,000	40,000
Borrowings under San Mateo Credit Facility	288,000	220,000
Senior unsecured notes payable	1,039,416	1,037,837
Asset retirement obligations	35,592	29,736
Derivative instruments	1,984	83
Deferred income taxes	37,329	13,221
Other long-term liabilities	43,131	4,962
Total long-term liabilities	1,700,452	1,345,839
Shareholders' equity
Common stock — $0.01 par value, 160,000,000 shares authorized; 116,644,246 and 116,374,503 shares issued; and 116,642,899 and 116,353,590 shares outstanding, respectively	1,166	1,164
Additional paid-in capital	1,981,014	1,924,408
Accumulated deficit	(148,500)	(236,277)
Treasury stock, at cost, 1,347 and 20,913 shares, respectively	(26)	(415)
Total shareholders' equity	1,833,654	1,688,880
Non-controlling interest in subsidiaries	135,798	90,777
Total shareholders’ equity	1,969,452	1,779,657
Total liabilities and shareholders’ equity	$ 4,069,676	$ 3,455,518