Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2017

Summary of Property and Equipment Including Oil and Natural Gas Properties

A summary of property and equipment including oil and natural gas properties is as follows (in thousands):

	June 30, 2017			December 31, 2016
Oil and natural gas properties:
Unproved	$	492,058		$	526,270
Proved		1,749,430			1,545,860
Gross oil and natural gas properties		2,241,488			2,072,130
Less accumulated depreciation depletion and amortization		(1,181,706	)		(1,131,378	)
Oil and natural gas properties, net		1,059,782			940,752
Other property and equipment		11,983			11,447
Less accumulated depreciation		(5,712	)		(4,699	)
Other property and equipment, net		6,271			6,748
Property and equipment, net	$	1,066,053		$	947,500

Changes in Company's Asset Retirement Obligation Liability

The following table sets forth the changes in the Company’s ARO liability for the six months ended June 30, 2017 (in thousands):

	Six Months Ended June 30, 2017
Asset retirement obligations, beginning of period	$	4,806
Additional liabilities incurred		540
Accretion		252
Asset retirement obligations, end of period	$	5,598

Summary of Reconciliation of Amounts in Previously Reported Consolidated Financial Statements

A reconciliation of the effects of the revision to amounts in the previously reported consolidated financial statements is as follows (in thousands, except per share amounts):

	As of  December 31, 2016
	As Reported			Adjustment			As Adjusted
Balance Sheet
Accounts receivable	$	43,638		$	785		$	44,423
Total current assets		249,630			785			250,415
Total assets		1,197,859			785			1,198,644
Accrued liabilities		64,150			(9,106	)		55,044
Total current liabilities		140,625			(9,106	)		131,519
Total liabilities		651,143			(9,106	)		642,037
Accumulated deficit		(1,414,561	)		9,891			(1,404,670	)
Total stockholders' equity		546,716			9,891			556,607
Total liabilities and stockholders' equity		1,197,859			785			1,198,644

	As of  December 31, 2016
	As Reported			Adjustment		As Adjusted
Statement of Stockholders' Equity
Accumulated deficit	$	(1,414,561	)	$	9,891	$	(1,404,670	)
Total stockholders' equity		546,716			9,891		556,607

	Three Months Ended June 30, 2016
	As Reported			Adjustment			As Adjusted
Statement of Operations and Comprehensive Income    (Loss)
Production and ad valorem taxes	$	2,051		$	152		$	2,203
Total operating expenses		83,865			152			84,017
Operating loss		(36,799	)		(152	)		(36,951	)
Loss before income taxes		(73,011	)		(152	)		(73,163	)
Net loss		(73,011	)		(152	)		(73,163	)
Basic and diluted loss per share	$	(0.33	)	$	—		$	(0.33	)

	Six Months Ended June 30, 2016
	As Reported			Adjustment			As Adjusted
Statement of Operations and Comprehensive Income    (Loss)
Production and ad valorem taxes	$	(233	)	$	4,999		$	4,766
Total operating expenses		179,232			4,999			184,231
Operating loss		(82,560	)		(4,999	)		(87,559	)
Loss before income taxes		(113,158	)		(4,999	)		(118,157	)
Net loss		(113,698	)		(4,999	)		(118,697	)
Basic and diluted loss per share	$	(0.51	)	$	(0.02	)	$	(0.53	)

	As of June 30, 2016
	As Reported			Adjustment			As Adjusted
Statement of Cash Flows
Net loss	$	(113,698	)	$	(4,999	)	$	(118,697	)
Accounts receivable		(1,238	)		(357	)		(1,595	)
Accounts payable and accrued liabilities		(13,026	)		5,356			(7,670	)

Accounts Receivable [Member] | Product Concentration Risk [Member]

Concentration Risk

The following table summarizes the Company’s concentration of receivables, net of allowances, by product or service as of June 30, 2017 and December 31, 2016 (in thousands):

	June 30, 2017		December 31, 2016
Receivables by product or service:
Sale of oil and natural gas and related products    and services	$	38,829	$	41,398
Joint interest owners		1,467		2,850
Derivatives		129		122
Other		13		53
Total	$	40,438	$	44,423