Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 17,782	$ 16,631
Restricted cash	1,573	1,638
Oil and gas revenue receivable	69,638	86,487
Joint interest billing and other receivables	20,603	16,616
Derivative assets	25,118	16,865
Income tax receivable	6,431	10,091
Inventory	18,962	13,450
Other current assets	4,161	5,647
Total current assets	164,268	167,425
Oil and gas properties, net, using the full cost method of accounting:
Proven	1,415,948	1,325,068
Property, plant and equipment, net	10,215	9,569
Other assets	14,959	10,920
Total assets	1,605,390	1,512,982
Current liabilities:
Accounts payable	54,688	59,951
Accrued liabilities	72,628	80,268
Production taxes payable	74,974	51,352
Interest payable	41,578	24,406
Derivative liabilities	21,036
Capital cost accrual	24,434	32,513
Total current liabilities	289,338	248,490
Long-term debt	2,118,515	2,116,211
Deferred gain on sale of liquids gathering system	102,551	105,189
Other long-term obligations	191,721	197,728
Total liabilities	2,702,125	2,667,618
Commitments and contingencies (Note 9)
Shareholders' equity:
Common stock - no par value; authorized - unlimited; issued and outstanding - 197,053,583 and 196,346,736 at March 31, 2018 and December 31, 2017, respectively	2,126,727	2,116,018
Treasury stock	(49)	(49)
Retained loss	(3,223,413)	(3,270,605)
Total shareholders' deficit	(1,096,735)	(1,154,636)
Total liabilities and shareholders' equity	$ 1,605,390	$ 1,512,982