Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
CURRENT ASSETS
Cash and cash equivalents	$ 97,075	$ 201,229
Accounts receivable	40,438	44,423
Assets held for sale	404	468
Other current assets	4,426	4,295
Total current assets	142,343	250,415
Oil and natural gas properties, successful efforts method:
Unproved properties	492,058	526,270
Proved oil and gas properties, net	567,724	414,482
Other property and equipment, net	6,271	6,748
Total property and equipment, net	1,066,053	947,500
OTHER NONCURRENT ASSETS
Other assets	3,861	729
TOTAL ASSETS	1,212,257	1,198,644
CURRENT LIABILITIES
Accounts payable	56,623	44,049
Accrued capital expenditures	15,329	11,083
Accrued liabilities	20,174	55,044
Accrued interest payable	21,239	21,098
Liabilities held for sale	189	245
Total current liabilities	113,554	131,519
NONCURRENT LIABILITIES
Debt, net of unamortized discount and debt issuance costs	493,644	492,278
Asset retirement obligations	5,598	4,806
Other liabilities	2,156	13,434
Total liabilities	614,952	642,037
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY
Preferred stock, 50,000,000 authorized, no shares issued and outstanding
Common stock, $0.01 par value, 1,000,000,000 authorized, 262,738,442 and 260,591,893 shares issued and outstanding, respectively	2,637	2,607
Additional paid in capital	1,963,090	1,958,731
Treasury stock, shares at cost; 991,247 and 72,704 shares, respectively	(2,093)	(61)
Accumulated deficit	(1,366,329)	(1,404,670)
Total stockholders' equity	597,305	556,607
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 1,212,257	$ 1,198,644