Bill Barrett (BBG) 10-Q 6 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Oct. 17, 2014
Document Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'BBG	'
Entity Registrant Name	'BILL BARRETT CORPORATION	'
Entity Central Index Key	'0001172139	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	49,650,853

CONSOLIDATED_BALANCE_SHEETS_UN

CONSOLIDATED BALANCE SHEETS (UNAUDITED) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$294,778	$54,595
Accounts receivable, net of allowance for doubtful accounts	88,554	97,586
Derivative assets	11,095	173
Prepayments and other current assets	3,515	4,893
Total current assets	397,942	157,247
Property and equipment - at cost, successful efforts method for oil and gas properties:	'	'
Proved oil and gas properties	1,863,478	2,863,923
Unproved oil and gas properties, excluded from amortization	282,822	296,599
Furniture, equipment and other	38,968	41,726
Property, plant and equipment, gross	2,185,268	3,202,248
Accumulated depreciation, depletion, amortization and impairment	-469,015	-999,752
Total property and equipment, net	1,716,253	2,202,496
Deferred financing costs and other noncurrent assets	23,089	21,770
Total	2,137,284	2,381,513
Current liabilities:	'	'
Accounts payable and accrued liabilities	154,920	115,928
Amounts payable to oil and gas property owners	28,510	26,778
Production taxes payable	45,690	39,235
Derivative liabilities	0	5,988
Deferred income taxes	4,065	199
Current portion of long-term debt	441	4,591
Total current liabilities	233,626	192,719
Long-term debt	828,624	979,082
Asset retirement obligations	19,569	39,200
Deferred income taxes	113,524	161,326
Derivatives and other noncurrent liabilities	2,997	3,468
Stockholders' equity:	'	'
Common stock, $0.001 par value; authorized 150,000,000 shares; 49,660,677 and 49,152,448 shares issued and outstanding at September 30, 2014 and December 31, 2013, respectively, with 1,588,591 and 1,340,060 shares subject to restrictions, respectively	48	48
Additional paid-in capital	912,026	904,261
Retained earnings	26,756	100,740
Treasury stock, at cost: zero shares at September 30, 2014 and December 31, 2013, respectively	0	0
Accumulated other comprehensive income	114	669
Total stockholders' equity	938,944	1,005,718
Total liabilities and stockholders' equity	$2,137,284	$2,381,513

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]	'	'
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	49,660,677	49,152,448
Common stock, shares outstanding (in shares)	49,660,677	49,152,448
Common stock, shares subject to restrictions (in shares)	1,588,591	1,340,060
Treasury stock, shares (in shares)	0	0

CONSOLIDATED_STATEMENTS_OF_OPE

CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Operating and Other Revenues:	'	'	'	'
Oil, gas and NGL production	$134,342	$149,345	$397,731	$424,130
Other	921	-790	7,658	5,001
Total operating and other revenues	135,263	148,555	405,389	429,131
Operating Expenses:	'	'	'	'
Lease operating expense	16,284	18,280	48,367	53,138
Gathering, transportation and processing expense	10,784	16,374	34,238	50,734
Production tax expense	10,495	8,183	27,770	21,915
Exploration expense	23	-24	442	212
Impairment, dry hole costs and abandonment expense	29,109	219,363	32,613	227,646
Loss on Divestitures	99,466	0	96,896	0
Depreciation, depletion and amortization	69,024	72,047	189,426	214,792
General and administrative expense	11,111	14,402	41,039	48,257
Total operating expenses	246,296	348,625	470,791	616,694
Operating Loss	-111,033	-200,070	-65,402	-187,563
Other Income and Expense:	'	'	'	'
Interest and other income	264	52	991	123
Interest expense	-18,033	-20,078	-53,285	-69,346
Commodity derivative gain (loss)	72,299	-25,595	369	-18,607
Gains (Losses) on Extinguishment of Debt	0	-21,460	0	-21,460
Total other income and expense	54,530	-67,081	-51,925	-109,290
Loss before Income Taxes	-56,503	-267,151	-117,327	-296,853
Benefit from Income Taxes	-21,854	-100,495	-43,343	-111,319
Net Loss	($34,649)	($166,656)	($73,984)	($185,534)
Net Income (Loss) Per Common Share, Basic (in dollars per share)	($0.72)	($3.51)	($1.54)	($3.91)
Net Income (Loss) Per Common Share, Diluted (in dollars per share)	($0.72)	($3.51)	($1.54)	($3.91)
Weighted Average Common Shares Outstanding, Basic (in shares)	48,060,086	47,535,124	47,982,992	47,452,865
Weighted Average Common Shares Outstanding, Diluted (in shares)	48,060,086	47,535,124	47,982,992	47,452,865

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'	'
Net Loss	($34,649)	($166,656)	($73,984)	($185,534)	($192,733)
Other Comprehensive Loss, net of tax:	'	'	'	'	'
Effect of derivative financial instruments	-219	-1,186	-555	-3,688	-4,663
Other comprehensive loss	-219	-1,186	-555	-3,688	'
Comprehensive Loss	($34,868)	($167,842)	($74,539)	($189,222)	'

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Operating Activities:	'	'
Net Loss	($73,984)	($185,534)
Adjustments to reconcile to net cash provided by operations:	'	'
Depreciation, depletion and amortization	189,426	214,792
Deferred income tax benefit	-43,604	-110,036
Impairment, dry hole costs and abandonment expense	32,613	227,646
Total commodity derivative (gain) loss	-369	18,607
Settlements of commodity derivatives	-21,580	2,971
Stock compensation and other non-cash charges	9,651	12,681
Amortization of debt discounts and deferred financing costs	3,200	4,535
Gains (Losses) on Extinguishment of Debt	0	21,460
(Gain) Loss on sale of properties	96,896	-3,102
Change in operating assets and liabilities:	'	'
Accounts receivable	9,025	12,343
Prepayments and other assets	914	1,475
Accounts payable, accrued and other liabilities	20,723	-24,801
Amounts payable to oil and gas property owners	1,936	6,510
Production taxes payable	6,455	-3,245
Net cash provided by operating activities	231,302	196,302
Investing Activities:	'	'
Additions to oil and gas properties, including acquisitions	-425,978	-335,597
Additions of furniture, equipment and other	-2,110	-1,506
Proceeds from sale of properties and other investing activities	557,747	784
Net cash provided by (used in) investing activities	129,659	-336,319
Financing Activities:	'	'
Proceeds from debt	165,000	390,000
Principal payments on debt	-283,442	-269,125
Proceeds from stock option exercises	126	1,653
Deferred financing costs and other	-2,462	-1,426
Net cash provided by (used in) financing activities	-120,778	121,102
Increase (Decrease) in Cash and Cash Equivalents	240,183	-18,915
Beginning Cash and Cash Equivalents	54,595	79,445
Ending Cash and Cash Equivalents	$294,778	$60,530

CONSOLIDATED_STATEMENTS_OF_STO

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED) (USD $)	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income
In Thousands, unless otherwise specified
Balance at Dec. 31, 2012	$1,182,775	$47	$883,923	$293,473	$0	$5,332
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Exercise of options, restricted stock activity and shares exchanged for exercise and tax withholding	4,607	1	6,384	'	-1,778	'
APIC pool for excess tax benefits related to share-based compensation	-1,259	'	-1,259	'	'	'
Stock-based compensation	16,991	'	16,991	'	'	'
Retirement of treasury stock	0	'	-1,778	'	1,778	'
Net income (loss)	-192,733	'	'	-192,733	'	'
Effect of derivative financial instruments, net of taxes	-4,663	'	'	'	'	-4,663
Balance at Dec. 31, 2013	1,005,718	48	904,261	100,740	0	669
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Exercise of options, restricted stock activity and shares exchanged for exercise and tax withholding	-2,336	'	126	'	-2,462	'
Stock-based compensation	10,101	'	10,101	'	'	'
Retirement of treasury stock	0	'	-2,462	'	2,462	'
Net income (loss)	-73,984	'	'	-73,984	'	'
Effect of derivative financial instruments, net of taxes	-555	'	'	'	'	-555
Balance at Sep. 30, 2014	$938,944	$48	$912,026	$26,756	$0	$114

CONSOLIDATED_STATEMENTS_OF_STO1

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Statement of Stockholders' Equity [Abstract]	'	'
Effect of derivative financial instruments, taxes	$334	$2,802

Organization

Organization	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Organization	'
	Organization
	Bill Barrett Corporation, a Delaware corporation, together with its wholly-owned subsidiaries (collectively, the "Company") is an independent oil and gas company engaged in the exploration, development and production of crude oil, natural gas and natural gas liquids ("NGLs"). Since its inception in January 2002, the Company has conducted its activities principally in the Rocky Mountain region of the United States.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	Summary of Significant Accounting Policies
	Basis of Presentation. The accompanying Unaudited Consolidated Financial Statements include the accounts of the Company. These statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP"). All intercompany accounts and transactions have been eliminated in consolidation. In the opinion of management, the accompanying financial statements include all adjustments (consisting of normal recurring accruals and adjustments) necessary to present fairly, in all material respects, the Company's interim results. However, operating results for the periods presented are not necessarily indicative of the results that may be expected for the full year. The Company's Annual Report on Form 10-K includes certain definitions and a summary of significant accounting policies and should be read in conjunction with this Quarterly Report on Form 10-Q. Except as disclosed herein, there have been no material changes to the information disclosed in the notes to the consolidated financial statements included in the Company's 2013 Annual Report on Form 10-K.
	Use of Estimates. In the course of preparing the Company's financial statements in accordance with GAAP, management makes various assumptions, judgments and estimates to determine the reported amount of assets, liabilities, revenues and expenses and in the disclosure of commitments and contingencies. Changes in these assumptions, judgments and estimates will occur as a result of the passage of time and the occurrence of future events and, accordingly, actual results could differ from amounts initially established.
	Areas requiring the use of assumptions, judgments and estimates relate to the expected cash settlement of the Company's 5% Convertible Senior Notes due 2028 ("Convertible Notes") in computing diluted earnings per share, volumes of oil, natural gas and NGL reserves used in calculating depreciation, depletion and amortization ("DD&A"), the amount of expected future cash flows used in determining possible impairments of oil and gas properties and the amount of future capital costs used in these calculations. Assumptions, judgments and estimates also are required in determining asset retirement obligations, the timing of dry hole costs, impairments of undeveloped properties, valuing deferred tax assets and estimating fair values of derivative instruments and stock-based compensation awards.
	Accounts Receivable. Accounts receivable is comprised of the following:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Accrued oil, gas and NGL sales	$	58,175			$	67,583
	Due from joint interest owners	25,339				23,507
	Other	5,054				6,517
	Allowance for doubtful accounts	(14		)		(21		)
	Total accounts receivable	$	88,554			$	97,586
	Oil and Gas Properties. The Company's oil, gas and NGL exploration and production activities are accounted for using the successful efforts method. Under this method, all property acquisition costs and costs of exploratory and development wells are capitalized when incurred, pending determination of whether the well has found proved reserves. If an exploratory well does not find proved reserves, the costs of drilling the well are charged to expense and remain within cash flows from investing activities in the Unaudited Consolidated Statements of Cash Flows. If an exploratory well does find proved reserves, the costs remain capitalized and are included within additions to oil and gas properties and remain within cash flows from investing activities in the Unaudited Consolidated Statements of Cash Flows when incurred. The costs of development wells are capitalized whether proved reserves are added or not. Oil and gas lease acquisition costs are also capitalized. Upon sale or retirement of depreciable or depletable property, the cost and related accumulated DD&A are eliminated from the accounts and the resulting gain or loss is recognized.
	Other exploration costs, including certain geological and geophysical expenses and delay rentals for oil and gas leases, are charged to expense as incurred. The sale of a partial interest in a proved property is accounted for as a cost recovery and no gain or loss is recognized as long as this treatment does not significantly affect the unit-of-production amortization rate. Maintenance and repairs are charged to expense, and renewals and betterments are capitalized to the appropriate property and equipment accounts.
	Unproved oil and gas property costs are transferred to proved oil and gas properties if the properties are subsequently determined to be productive or are assigned proved reserves. Proceeds from sales of partial interests in unproved leases are accounted for as a recovery of cost without recognizing any gain until all costs are recovered. Unproved oil and gas properties are assessed periodically for impairment based on remaining lease terms, drilling results, reservoir performance, commodity price outlooks, future plans to develop acreage and other relevant matters.
	Materials and supplies consist primarily of tubular goods and well equipment to be used in future drilling operations or repair operations and are carried at the lower of cost or market value, on a first-in, first-out basis.
	The following table sets forth the net capitalized costs and associated accumulated DD&A and non-cash impairments relating to the Company's oil, natural gas and NGL producing activities:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Proved properties	$	382,867			$	485,427
	Wells and related equipment and facilities	1,406,678				2,192,754
	Support equipment and facilities	60,588				177,224
	Materials and supplies	13,345				8,518
	Total proved oil and gas properties	$	1,863,478			$	2,863,923
	Unproved properties	185,237				239,925
	Wells and facilities in progress	97,585				56,674
	Total unproved oil and gas properties, excluded from amortization	$	282,822			$	296,599
	Accumulated depreciation, depletion, amortization and impairment	(443,748		)		(976,339		)
	Total oil and gas properties, net	$	1,702,552			$	2,184,183
	All exploratory wells are evaluated for economic viability within one year of well completion. Exploratory wells that discover potentially economic reserves in areas where a major capital expenditure would be required before production could begin, and where the economic viability of that major capital expenditure depends upon the successful completion of further exploratory work in the area, remain capitalized if the well finds a sufficient quantity of reserves to justify its completion as a producing well and the Company is making sufficient progress assessing the reserves and the economic and operating viability of the project. As of September 30, 2014 and December 31, 2013, there were no exploratory well costs that had been capitalized for a period greater than one year since the completion of drilling.
	The Company reviews proved oil and gas properties on a field-by-field basis for impairment on a quarterly basis or whenever events and circumstances indicate that a decline in the recoverability of their carrying value may have occurred. The Company estimates the expected undiscounted future cash flows of its oil and gas properties and compares such undiscounted future cash flows to the carrying amount of the oil and gas properties to determine if the carrying amount is recoverable. If the carrying value of a property exceeds the undiscounted future cash flows, the Company will impair the carrying value to fair value based on an analysis of quantitative and qualitative factors. The Company has no guarantee that the undiscounted future cash flows analysis of its proved property represents the applicable market value. The factors used to determine fair value include, but are not limited to, recent sales prices of comparable properties, the present value of future revenues, net of estimated operating and development costs using estimates of reserves, future commodity pricing, future production estimates, anticipated capital expenditures and various discount rates commensurate with the risk and current market conditions associated with realizing the expected cash flows projected.
	The Company recognized non-cash impairment charges, which were included within impairment, dry hole costs and abandonment expense in the Unaudited Consolidated Statements of Operations, as follows:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
		(in thousands)
	Non-cash impairment of proved oil and gas properties	$	11,493		(1)	$	198,787		(2)	$	12,531		(3)	$	198,787		(2)
	Non-cash impairment of unproved oil and gas properties	15,250			(1)	17,777			(2)	15,250			(3)	17,777			(2)
	Non-cash impairment of inventory	—				—				340				—
	Dry hole costs	3				(36		)		96				928
	Abandonment expense	2,363				2,835				4,396				10,154
	Total non-cash impairment, dry hole costs and abandonment expense	$	29,109			$	219,363			$	32,613			$	227,646
	-1	As a result of the Powder River Oil Divestiture (see Note 4) and results of drilling and completion activity in the Paradox Basin during the three months ended September 30, 2014, the remaining carrying values of Powder River Oil and Paradox Basin assets were analyzed relative to their estimated fair market values. As a result, the Company recognized proved and unproved property impairments of $11.5 million and $15.3 million, respectively.
	-2	We classified certain oil and gas properties in the West Tavaputs field in the Uinta Basin as held for sale as of September 30, 2013 (see Note 4). Upon the classification as held for sale, the carrying value of the related properties was analyzed relative to the estimated fair value. As a result, we recognized $198.8 million of proved impairment expense and $2.5 million of unproved property impairment expense during the three and nine months ended September 30, 2013. In addition, we recognized $15.3 million of impairment expense related to certain unproved oil and gas properties within various exploration and development projects primarily as a result of no future plans to evaluate the remaining acreage and an estimated market value below our carrying value.
	-3	As a result of the Powder River Oil Divestiture and results of drilling and completion activity in the Paradox Basin during the nine months ended September 30, 2014, the remaining carrying values of Powder River Oil and Paradox Basin assets were analyzed relative to their estimated fair market values. As a result, the Company recognized proved and unproved property impairments of $11.5 million and $15.3 million, respectively. In addition, $1.0 million of proved impairment expense was incurred during the nine months ended September 30, 2014 related to the West Tavaputs Divestiture (see Note 4) based upon a true up of previously estimated fair value relative to carrying value.
	The provision for DD&A of oil and gas properties is calculated on a field-by-field basis using the unit-of-production method. Natural gas and NGLs are converted to an oil equivalent, Boe, at the standard rate of six Mcf to one Boe and forty-two gallons to one Boe, respectively. Estimated future dismantlement, restoration and abandonment costs are taken into consideration by this calculation.
	Accounts Payable and Accrued Liabilities. Accounts payable and accrued liabilities are comprised of the following:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Accrued drilling, completion and facility costs	$	85,517			$	54,750
	Accrued lease operating, gathering, transportation and processing expenses	13,025				17,317
	Accrued general and administrative expenses	7,042				14,605
	Trade payables and other	49,336				29,256
	Total accounts payable and accrued liabilities	$	154,920			$	115,928
	Environmental Liabilities. Environmental expenditures that relate to an existing condition caused by past operations and that do not contribute to current or future revenue generation are expensed. Environmental liabilities are accrued when environmental assessments and/or clean-ups are probable, and the costs can be reasonably estimated.
	Revenue Recognition. Oil, gas and NGL revenues are recognized when production is sold to a purchaser at a fixed or determinable price, when delivery has occurred and title has transferred, and collectability of the revenue is reasonably assured. The Company uses the sales method to account for gas and NGL imbalances. Under this method, revenues are recorded on the basis of gas and NGLs actually sold by the Company. In addition, the Company records revenues for its share of gas and NGLs sold by other owners that cannot be volumetrically balanced in the future due to insufficient remaining reserves. The Company also reduces revenues for other owners' gas and NGLs sold by the Company that cannot be volumetrically balanced in the future due to insufficient remaining reserves. The Company's remaining over- and under- produced gas and NGLs balancing positions are taken into account in determining the Company's proved oil, gas and NGL reserves. Imbalances at September 30, 2014 and 2013 were not material.
	Derivative Instruments and Hedging Activities. The Company periodically uses derivative financial instruments to achieve a more predictable cash flow from its oil, natural gas and NGL sales by reducing its exposure to price fluctuations. Derivative instruments are recorded at fair market value and are included in the Unaudited Consolidated Balance Sheets as assets or liabilities.
	Income Taxes. Income taxes are provided for the tax effects of transactions reported in the financial statements and consist of taxes currently payable plus deferred income taxes related to certain income and expenses recognized in different periods for financial and income tax reporting purposes. Deferred income tax assets and liabilities represent the future tax return consequences of those differences, which will either be taxable or deductible when assets are recovered or liabilities are settled. Deferred income taxes also include tax credits and net operating losses that are available to offset future income taxes. Deferred income taxes are measured by applying currently enacted tax rates.
	The Company accounts for uncertainty in income taxes for tax positions taken or expected to be taken in a tax return. Only tax positions that meet the more-likely-than-not recognition threshold are recognized.
	Earnings/Loss Per Share. Basic net income (loss) per common share is calculated by dividing net income (loss) attributable to common stock by the weighted average number of common shares outstanding during each period. Diluted net income per common share is calculated by dividing net income attributable to common stock by the weighted average number of common shares outstanding and other dilutive securities. Potentially dilutive securities for the diluted net income per common share calculations consist of nonvested equity shares of common stock, in-the-money outstanding stock options to purchase the Company's common stock and shares into which the Convertible Notes are convertible. No potential common shares are included in the computation of any diluted per share amount when a net loss exists, as was the case for the three and nine months ended September 30, 2014 and 2013.
	In satisfaction of its obligation upon conversion of the Convertible Notes, the Company may elect to deliver, at its option, cash, shares of its common stock or a combination of cash and shares of its common stock. As of September 30, 2014, the Company expected to settle the remaining Convertible Notes in cash. Therefore, the treasury stock method was used to measure the potentially dilutive impact of shares associated with that remaining conversion feature. The Company has the right with at least 30 days' notice to call the Convertible Notes and the holders have the right to require the Company to purchase the notes on March 20, 2015. The Convertible Notes have not been dilutive since their issuance in March 2008 and, therefore, did not impact the diluted net income (loss) per common share calculation for the three and nine months ended September 30, 2014 and 2013. The diluted net income (loss) per common share excludes the anti-dilutive effect of 1,336,252 and 2,450,539 shares of stock options and nonvested performance-based shares of common stock for the three months ended September 30, 2014 and 2013, and 1,199,451 and 2,731,578 shares of stock options and nonvested performance-based shares of common stock for the nine months ended September 30, 2014 and 2013, respectively.
	The following table sets forth the calculation of basic and diluted loss per share:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
	(in thousands, except per share amounts)
Net loss	$	(34,649	)		$	(166,656	)		$	(73,984	)		$	(185,534	)
Basic weighted-average common shares outstanding in period	48,060				47,535				47,983				47,453
Add dilutive effects of stock options and nonvested equity shares of common stock	—				—				—				—
Diluted weighted-average common shares outstanding in period	48,060				47,535				47,983				47,453
Basic net loss per common share	$	(0.72	)		$	(3.51	)		$	(1.54	)		$	(3.91	)
Diluted net loss per common share	$	(0.72	)		$	(3.51	)		$	(1.54	)		$	(3.91	)
New Accounting Pronouncements. In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers. The objective of this update is to clarify the principles for recognizing revenue and to develop a common revenue standard. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. The Company is currently evaluating the potential impact that the adoption will have on the Company’s disclosures and financial statements.
In June 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. The objective of this update is to provide guidance on the treatment of a performance target that could be achieved after the requisite service period. ASU 2014-12 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. The adoption of this standard will not have an impact on the Company's consolidated financial statements.
In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern. The objective of this update is to provide guidance in GAAP about management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern and to provide related footnote disclosures. ASU 2014-15 is effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. The adoption of this standard will not have an impact on the Company's consolidated financial statements.

Supplemental_Disclosures_of_Ca

Supplemental Disclosures of Cash Flow Information	9 Months Ended
	Sep. 30, 2014
Supplemental Cash Flow Elements [Abstract]	'
Supplemental Disclosures of Cash Flow Information	'
	Supplemental Disclosures of Cash Flow Information
	Supplemental cash flow information is as follows:
		Nine Months Ended September 30,
		2014			2013
		(in thousands)
	Cash paid for interest	$	36,267		$	61,796
	Cash paid for income taxes	1			1,861
	Supplemental disclosures of non-cash investing and financing activities:
	Current liabilities	90,381			75,265
	Net increase (decrease) in asset retirement obligations	(23,327		)	2,924
	Retirement of treasury stock	(2,462		)	(1,415		)
	Fair value of properties exchanged in non-cash transactions	77,078			—
	Relief from lease financing obligation	36,106			45,190

Divestitures

Divestitures	9 Months Ended
	Sep. 30, 2014
Discontinued Operations and Disposal Groups [Abstract]	'
Divestitures	'
	Divestitures
	On December 10, 2013, the Company completed the sale of its West Tavaputs natural gas assets in the Uinta Basin (the "West Tavaputs Divestiture"). The Company received $308.7 million in cash proceeds, after closing adjustments. The divestiture proceeds were subject to various purchase price adjustments incurred in the normal course of business and were finalized during 2014. The Company recognized an impairment loss of $1.0 million during the nine months ended September 30, 2014 related to these assets based upon a true up of previously estimated fair value relative to carrying value. An initial impairment loss of $209.5 million related to these assets was recognized during the year ended December 31, 2013.
	During the three months ended September 30, 2014, the Company completed the sale or exchange of the majority of its Powder River Basin assets (the "Powder River Oil Divestiture") in four separate transactions with effective dates of April 1, 2014 for net cash proceeds of $27.4 million, after initial closing adjustments. Three transactions involved the cumulative sale of 17,497 net mineral acres. The fourth transaction involved an exchange of 29,015 net mineral acres in the Powder River Basin for 7,856 net mineral acres within the southern block of the Company’s operated Northeast Wattenberg area of the Denver-Julesburg Basin, valued at $71.0 million. Assets sold or exchanged as part of the overall Powder River Oil Divestiture included $85.7 million in proved and $39.7 million in unproved oil and gas properties, net of accumulated depreciation, depletion, amortization and impairment of $33.1 million and $1.3 million in asset retirement obligations. A loss on sale of $25.7 million related to these transactions is included within operating expenses in the Unaudited Consolidated Statements of Operations for the three and nine months ended September 30, 2014. The divestiture proceeds are subject to various purchase price adjustments incurred in the normal course of business and will be finalized in early 2015.
	On September 30, 2014, the Company completed the sale of its Gibson Gulch natural gas program in the Piceance Basin (the "Piceance Divestiture") with an effective date of July 1, 2014. The Company received $503.6 million in cash proceeds, after initial closing estimates. In addition to the cash proceeds, the Company recognized non-cash proceeds of $22.4 million related to the relief of the Company's asset retirement obligation and $36.1 million related to relief from the Company's lease financing obligation described in Note 5 (the "Lease Financing Obligation"). A loss on sale of $74.8 million related to this transaction is included within operating expenses in the Unaudited Consolidated Statements of Operations for the three and nine months ended September 30, 2014. The divestiture proceeds are subject to various purchase price adjustments incurred in the normal course of business and will be finalized in early 2015. The carrying amounts by major asset class within the disposal group for the Piceance Divestiture are summarized below (in thousands):
	Assets:
	Proved properties	$	1,320,757
	Furniture, equipment and other	4,907
	Accumulated depreciation, depletion, amortization and impairment	(688,864		)
	Other assets	173
	Total assets	$	636,973
	Liabilities:
	Asset retirement obligation	$	22,448
	Lease financing obligation	36,106
	Total liabilities	$	58,554
	Net assets	$	578,419

LongTerm_Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Long-Term Debt	'
	Long-Term Debt
	The Company's outstanding debt is summarized below:
			As of September 30, 2014									As of December 31, 2013
		Maturity Date	Principal			Unamortized			Carrying			Principal		Unamortized		Carrying
						Discount			Amount					Discount		Amount
			(in thousands)
	Amended Credit Facility (1)	October 31, 2016	$	—		$	—		$	—		$	115,000	$	—	$	115,000
	Convertible Notes (2)	March 15, 2028 (3)	25,344			—			25,344			25,344		—		25,344
	7.625% Senior Notes (4)	October 1, 2019	400,000			—			400,000			400,000		—		400,000
	7.0% Senior Notes (5)	October 15, 2022	400,000			—			400,000			400,000		—		400,000
	Lease Financing Obligation (6)	August 10, 2020	3,721			—			3,721			43,329		—		43,329
	Total Debt		$	829,065		$	—		$	829,065		$	983,673	$	—	$	983,673
	Less: Current Portion of Long-Term Debt		441			—			441			4,591		—		4,591
	Total Long-Term Debt		$	828,624		$	—		$	828,624		$	979,082	$	—	$	979,082
	-1	The recorded value of the Amended Credit Facility approximates its fair value due to its floating rate structure.
	-2	The aggregate estimated fair value of the Convertible Notes was approximately $25.4 million and $25.1 million as of September 30, 2014 and December 31, 2013, respectively, based on reported market trades of these instruments.
	-3	The Company has the right at any time, with at least 30 days' notice, to call the Convertible Notes, and the holders have the right to require the Company to purchase the notes on each of March 20, 2015, March 20, 2018 and March 20, 2023.
	-4	The aggregate estimated fair value of the 7.625% Senior Notes was approximately $407.3 million and $430.2 million as of September 30, 2014 and December 31, 2013, respectively, based on reported market trades of these instruments.
	-5	The aggregate estimated fair value of the 7.0% Senior Notes was approximately $416.0 million and $417.0 million as of September 30, 2014 and December 31, 2013, respectively, based on reported market trades of these instruments.
	-6	The aggregate estimated fair value of the Lease Financing Obligation was approximately $3.5 million as of September 30, 2014, and $41.7 million as of December 31, 2013. The decrease in estimated fair value is primarily related to the sale of equipment in the West Tavaputs and Piceance Divestitures. Because there is no active, public market for the Lease Financing Obligation, the aggregate estimated fair value was based on market-based parameters of comparable term secured financing instruments.
	Amended Credit Facility
	The Company's Amended Credit Facility has a maturity date of October 31, 2016 and current commitments and borrowing base of $375.0 million. As of September 30, 2014, the Company had no amounts outstanding under the Amended Credit Facility. As credit support for future payment under a contractual obligation, a $26.0 million letter of credit has been issued under the Amended Credit Facility, which reduced the borrowing capacity of the Amended Credit Facility as of September 30, 2014 to $349.0 million.
	Interest rates are LIBOR plus applicable margins of 1.5% to 2.5% or ABR plus 0.5% to 1.5% and the commitment fee is between 0.375% to 0.5% based on borrowing base utilization. The average annual interest rates incurred on the Amended Credit Facility were 2.0% and 2.1% for the three months ended September 30, 2014 and 2013, and 1.9% and 2.0% for the nine months ended September 30, 2014 and 2013, respectively.
	The borrowing base is required to be re-determined twice per year. On September 30, 2014, the borrowing base was reduced to $375.0 million based on year-end 2013 reserves as adjusted for the Piceance and Powder River Oil Divestitures and the Company's hedge position. Future semi-annual borrowing bases will be computed based on proved oil, natural gas and NGL reserves, hedge positions and estimated future cash flows from those reserves, as well as any other outstanding debt of the Company.
	The Amended Credit Facility contains certain financial covenants. The Company is currently in compliance with all financial covenants and has complied with all financial covenants since issuance.
	5% Convertible Senior Notes Due 2028
	On March 12, 2008, the Company issued $172.5 million aggregate principal amount of Convertible Notes. On March 20, 2012, $147.2 million of the outstanding principal amount, or approximately 85% of the outstanding Convertible Notes, were put to the Company and redeemed by the Company at par. The Company settled the notes in cash. After the redemption, $25.3 million aggregate principal amount of the Convertible Notes was outstanding. The Convertible Notes mature on March 15, 2028, unless earlier converted, redeemed or purchased by the Company. The Convertible Notes are senior unsecured obligations and rank equal in right of payment to all of the Company's existing and future senior unsecured indebtedness, are senior in right of payment to all of the Company's future subordinated indebtedness, and are effectively subordinated to all of the Company's secured indebtedness with respect to the collateral securing such indebtedness. The Convertible Notes are structurally subordinated to all present and future secured and unsecured debt and other obligations of the Company's subsidiaries. The Convertible Notes are fully and unconditionally guaranteed by the subsidiaries that guarantee the Company's indebtedness under the Amended Credit Facility, the 7.625% Senior Notes and the 7.0% Senior Notes.
	The Convertible Notes bear interest at a rate of 5% per annum, payable semi-annually in arrears on March 15 and September 15 of each year. Holders of the remaining Convertible Notes may require the Company to purchase all or a portion of their Convertible Notes for cash on each of March 20, 2015, March 20, 2018 and March 20, 2023 at a purchase price equal to 100% of the principal amount of the Convertible Notes to be repurchased, plus accrued and unpaid interest, if any, up to but excluding the applicable purchase date. The Company has the right with at least 30 days' notice to call the Convertible Notes.
	7.625% Senior Notes Due 2019
	On September 27, 2011, the Company issued $400.0 million in principal amount of 7.625% Senior Notes due 2019 at par. The 7.625% Senior Notes mature on October 1, 2019. Interest is payable in arrears semi-annually on April 1 and October 1 beginning April 1, 2012. The 7.625% Senior Notes are senior unsecured obligations of the Company and rank equal in right of payment with all of the Company's other existing and future senior unsecured indebtedness, including the Company's Convertible Notes and 7.0% Senior Notes. The 7.625% Senior Notes are redeemable at the Company's option on October 1, 2015 at a redemption price of 103.813% of the principal amount of the notes. The 7.625% Senior Notes are fully and unconditionally guaranteed by the subsidiaries that guarantee the Company's indebtedness under the Amended Credit Facility, the Convertible Notes and the 7.0% Senior Notes. The 7.625% Senior Notes include certain covenants that limit the Company's ability to incur additional indebtedness, make restricted payments, create liens or sell assets and that prohibit the Company from paying dividends. The Company is currently in compliance with all financial covenants and has complied with all financial covenants since issuance.
	7.0% Senior Notes Due 2022
	On March 12, 2012, the Company issued $400.0 million in aggregate principal amount of 7.0% Senior Notes due 2022 at par. The 7.0% Senior Notes mature on October 15, 2022. Interest is payable in arrears semi-annually on April 15 and October 15 of each year. The 7.0% Senior Notes are senior unsecured obligations and rank equal in right of payment with all of the Company's other existing and future senior unsecured indebtedness, including the Company's Convertible Notes and 7.625% Senior Notes. The 7.0% Senior Notes are redeemable at the Company's option on October 15, 2017 at a redemption price of 103.5% of the principal amount of the notes. The 7.0% Senior Notes are fully and unconditionally guaranteed by the subsidiaries that guarantee the Company's indebtedness under the Amended Credit Facility, the Convertible Notes and the 7.625% Senior Notes. The 7.0% Senior Notes include certain covenants that limit the Company's ability to incur additional indebtedness, make restricted payments, create liens or sell assets and that prohibit the Company from paying dividends. The Company is currently in compliance with all financial covenants and has complied with all financial covenants since issuance.
	Lease Financing Obligation Due 2020
	On July 23, 2012, the Company entered into the Lease Financing Obligation, whereby the Company received $100.8 million through the sale and subsequent leaseback of existing compressors and related facilities owned by the Company. The Lease Financing Obligation expires on August 10, 2020, and the Company has the option to purchase the equipment at the end of the lease term for the then current fair market value. The Lease Financing Obligation also contains an early buyout option where the Company may purchase the equipment for $36.6 million on February 10, 2019. The lease payments related to the equipment are recognized as principal and interest expense based on a weighted average implicit interest rate of 3.3%. See Note 11 for discussion of aggregate minimum future lease payments. As the result of the disposition of equipment in the West Tavaputs Divestiture and the Piceance Divestiture, the Company's remaining Lease Financing Obligation has been reduced to $3.7 million as of September 30, 2014 and the early buyout option has been reduced to $1.8 million.
	The following table summarizes, for the periods indicated, the cash or accrued portion of interest expense related to the Amended Credit Facility, the 9.875% Senior Notes that were redeemed in full on July 15, 2013, Convertible Notes, 7.625% Senior Notes, 7.0% Senior Notes and the Lease Financing Obligation along with the non-cash portion resulting from the amortization of the debt discount and transaction costs through interest expense:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
		(in thousands)
	Amended Credit Facility (1)
	Cash interest	$	1,771		$	2,296		$	4,392		$	4,211
	Non-cash interest	$	586		$	585		$	1,757		$	1,756
	9.875% Senior Notes (2)
	Cash interest	$	—		$	1,029		$	—		$	13,373
	Non-cash interest	$	—		$	—		$	—		$	1,361
	Convertible Notes (3)
	Cash interest	$	306		$	310		$	940		$	943
	Non-cash interest	$	1		$	1		$	4		$	4
	7.625% Senior Notes (4)
	Cash interest	$	7,625		$	7,625		$	22,875		$	22,875
	Non-cash interest	$	273		$	272		$	817		$	798
	7.0% Senior Notes (5)
	Cash interest	$	7,000		$	7,000		$	21,000		$	21,000
	Non-cash interest	$	204		$	203		$	610		$	592
	Lease Financing Obligation (6)
	Cash interest	$	248		$	750		$	765		$	2,305
	Non-cash interest	$	3		$	8		$	11		$	24
	-1	Cash interest includes amounts related to interest and commitment fees paid on the Amended Credit Facility and participation and fronting fees paid on the letter of credit.
	-2	The stated interest rate for the 9.875% Senior Notes was 9.875% per annum with an effective interest rate of 11.2% per annum. The Company redeemed the 9.875% Senior Notes in full on July 15, 2013.
	-3	The stated interest rate for the Convertible Notes is 5% per annum. The effective interest rate of the Convertible Notes includes amortization of the debt discount, which represented the fair value of the equity conversion feature at the time of issue. The stated interest rate of 5% on the Convertible Notes will be the effective interest rate of the $25.3 million remaining principal balance, as the related debt discount was fully amortized as of March 31, 2012.
	-4	The stated interest rate for the 7.625% Senior Notes is 7.625% per annum with an effective interest rate of 8.0% per annum.
	-5	The stated interest rate for the 7.0% Senior Notes is 7.0% per annum with an effective interest rate of 7.2% per annum.
	-6	The effective interest rate for the Lease Financing Obligation is 3.3% per annum. The decrease in cash interest from $0.8 million to $0.2 million for the three months ended September 30, 2013 and September 30, 2014, respectively, and from $2.3 million to $0.8 million for the nine months ended September 30, 2013 and September 30, 2014, respectively, is due to the West Tavaputs Divestiture. The purchaser assumed approximately 51% of the Lease Financing Obligation, including the buyout option, related to West Tavaputs equipment.

Asset_Retirement_Obligations

Asset Retirement Obligations	9 Months Ended
	Sep. 30, 2014
Asset Retirement Obligation Disclosure [Abstract]	'
Asset Retirement Obligations	'
	Asset Retirement Obligations
	A reconciliation of the Company's asset retirement obligations for the nine months ended September 30, 2014 is as follows (in thousands):
	As of December 31, 2013	$	43,005
	Liabilities incurred	3,627
	Liabilities settled	(4,383		)
	Disposition of properties	(23,722		)
	Accretion expense	2,532
	Revisions to estimate	1,151
	As of September 30, 2014	$	22,210
	Less: Current asset retirement obligations	2,641
	Long-term asset retirement obligations	$	19,569

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Fair Value Measurements
	Assets and Liabilities Measured on a Recurring Basis
	The Company's financial instruments, including cash and cash equivalents, accounts and notes receivable and accounts payable are carried at cost, which approximates fair value due to the short-term maturity of these instruments. The recorded value of the Amended Credit Facility, as discussed in Note 5, approximates its fair value due to its floating rate structure based on the LIBOR spread and the Company's borrowing base utilization.
	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). The Company utilizes a mid-market pricing convention (the mid-point price between bid and ask prices) for valuation as a practical expedient for assigning fair value. The Company uses market data or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk. These inputs can be readily observable, market corroborated or generally unobservable. The Company primarily applies the market and income approaches for recurring fair value measurements and utilizes the best available information. Given the Company's historical market transactions, its markets and instruments are fairly liquid. Therefore, the Company has been able to classify fair value balances based on the observability of those inputs. A fair value hierarchy was established that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements).
	Level 1 – Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 1 primarily consists of financial instruments such as exchange-traded derivatives, listed securities and U.S. government treasury securities.
	Level 2 – Pricing inputs are other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the reporting date. Level 2 includes those financial instruments that are valued using models or other valuation methodologies. These models are primarily industry-standard models that consider various assumptions, including quoted forward prices for commodities, time value, volatility factors and current market and contractual prices for the underlying instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace throughout the full term of the instrument, can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. Instruments in this category include non-exchange-traded derivatives such as over-the-counter forwards and options.
	Level 3 – Pricing inputs include significant inputs that are generally less observable than objective sources. These inputs may be used with internally developed methodologies that result in management's best estimate of fair value. At each balance sheet date, the Company performs an analysis of all applicable instruments and includes in Level 3 all of those whose fair value is based on significant unobservable inputs.
	The following tables set forth by level within the fair value hierarchy the Company's financial assets and financial liabilities that were measured at fair value on a recurring basis. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company's assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of assets and liabilities and their placement within the fair value hierarchy levels.
		As of September 30, 2014
		Level 1		Level 2		Level 3		Total
		(in thousands)
	Assets
	Deferred Compensation Plan	$	914	$	—	$	—	$	914
	Cash Equivalents - Money Market Funds	53		—		—		53
	Commodity Derivatives	—		20,530		—		20,530
	Liabilities
	Commodity Derivatives	$	—	$	2,757	$	—	$	2,757
		As of December 31, 2013
		Level 1		Level 2		Level 3		Total
		(in thousands)
	Assets
	Deferred Compensation Plan	$	941	$	—	$	—	$	941
	Cash Equivalents - Money Market Funds	53		—		—		53
	Commodity Derivatives	—		11,483		—		11,483
	Liabilities
	Commodity Derivatives	$	—	$	14,771	$	—	$	14,771
	All fair values reflected in the table above and in the Unaudited Consolidated Balance Sheets have been adjusted for non-performance risk. For applicable financial assets carried at fair value, the credit standing of the counterparties is analyzed and factored into the fair value measurement of those assets. In addition, the fair value measurement of a liability has been adjusted to reflect the nonperformance risk of the Company. The following methods and assumptions were used to estimate the fair values of the assets and liabilities in the table above.
	Level 1 Fair Value Measurements – The Company maintains a non-qualified deferred compensation plan (as discussed in more detail in Note 10) which allows certain management employees to defer receipt of a portion of their compensation. The Company maintains assets for the deferred compensation plan in a rabbi trust. The assets of the rabbi trust are invested in publicly traded mutual funds and are recorded in other current and other long-term assets in the Unaudited Consolidated Balance Sheets. The Company also has highly liquid short term investments in money market funds. The deferred compensation plan financial assets are reported at fair value based on active market quotes, which represent Level 1 inputs. The money market fund investments are recorded at carrying value, which approximates fair value, which represent Level 1 inputs. The fair values of the Company's fixed rate 7.625% Senior Notes and 7.0% Senior Notes totaled $823.3 million as of September 30, 2014. The fair values of the Company's fixed rate 7.625% Senior Notes and 7.0% Senior Notes totaled $847.2 million as of December 31, 2013. The fair values of the Company's fixed rate Senior Notes are based on active market quotes, which represent Level 1 inputs.
	Level 2 Fair Value Measurements – The fair value of crude oil, natural gas and NGL forwards and options are estimated using a combined income and market valuation methodology with a mid-market pricing convention based upon forward commodity price and volatility curves. The curves are obtained from independent pricing services reflecting broker market quotes. The Company did not make any adjustments to the obtained curves. The pricing services publish observable market information from multiple brokers and exchanges. No proprietary models are used by the pricing services for the inputs. The Company utilized the counterparties' valuations to assess the reasonableness of the Company's valuations.
	There is no active, public market for the Company's Amended Credit Facility, Convertible Notes or Lease Financing Obligation. The Amended Credit Facility balance of zero and $115.0 million as of September 30, 2014 and December 31, 2013, respectively, approximates its fair value due to its floating rate structure. The Convertible Notes fair value of $25.4 million and $25.1 million as of September 30, 2014 and December 31, 2013, respectively, are measured based on market-based parameters of the various components of the Convertible Notes and over the counter trades. The Lease Financing Obligation fair values of $3.5 million and $41.7 million as of September 30, 2014 and December 31, 2013, respectively, are measured based on market-based parameters of comparable term secured financing instruments. The fair value measurements for the Amended Credit Facility, Convertible Notes and Lease Financing Obligation represent Level 2 inputs.
	Level 3 Fair Value Measurements – As of September 30, 2014 and December 31, 2013, the Company did not have assets or liabilities that were measured on a recurring basis classified under a Level 3 fair value hierarchy.
	Assets and Liabilities Measured on a Non-recurring Basis – The Company utilizes fair value on a non-recurring basis to perform impairment tests on its property and equipment when required. The inputs used to determine such fair value are primarily based upon internally developed cash flow models and are classified within Level 3. During the three months ended September 30, 2014 and 2013, the Company recorded impairment charges of $26.7 million and $216.6 million, respectively, on proved and unproved oil and gas properties. During the nine months ended September 30, 2014 and 2013, the Company recorded impairment charges of $27.8 million and $216.6 million, respectively, on proved and unproved oil and gas properties. See Note 2 for additional details related to impairment expense recognized during these periods.
	The Company also applied fair value accounting guidance to measure the assets and liabilities in the Piceance Divestiture and Powder River Oil Divestiture (see Note 4). The fair values of these items were primarily determined using the accepted offers from third-party purchasers. Because of the unobservable nature of these inputs, they are classified within Level 3.

Derivative_Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Instruments	'
	Derivative Instruments
	The Company uses financial derivative instruments as part of its price risk management program to achieve a more predictable cash flow from its production revenues by reducing its exposure to commodity price fluctuations. The Company has entered into financial commodity swap contracts related to the sale of a portion of the Company's production. The Company does not enter into derivative instruments for speculative or trading purposes.
	In addition to financial contracts, the Company may at times be party to various physical commodity contracts for the sale of oil, natural gas and NGLs that have varying terms and pricing provisions. These physical commodity contracts qualify for the normal purchase and normal sale exception and, therefore, are not subject to hedge or mark-to-market accounting. The financial impact of physical commodity contracts is included in oil, natural gas and NGL production revenues at the time of settlement.
	All derivative instruments, other than those that meet the normal purchase and normal sale exception, as mentioned above, are recorded at fair value and included in the Unaudited Consolidated Balance Sheets as assets or liabilities. The following table summarizes the location, as well as the gross and net fair value amounts of all derivative instruments presented in the Unaudited Consolidated Balance Sheets as of the dates indicated.
		As of September 30, 2014
	Balance Sheet	Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Assets Presented in the
		Derivative Assets				Sheet				Balance Sheet
		(in thousands)
	Derivative assets	$	13,623			$	(2,528	)	(1)	$	11,095
	Deferred financing costs and other noncurrent assets	6,907				(229		)	(1)	6,678			(3)
	Total derivative assets	$	20,530			$	(2,757	)		$	17,773
		Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Liabilities Presented in
		Derivative				Sheet				the Balance Sheet
		Liabilities
		(in thousands)
	Derivative liabilities	$	(2,528	)		$	2,528		(2)	$	—
	Derivatives and other noncurrent liabilities	(229		)		229			(2)	—			(4)
	Total derivative liabilities	$	(2,757	)		$	2,757			$	—
		As of December 31, 2013
	Balance Sheet	Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Assets Presented in the
		Derivative Assets				Sheet				Balance Sheet
		(in thousands)
	Derivative assets	$	8,259			$	(8,086	)	(1)	$	173
	Deferred financing costs and other noncurrent assets	3,224				(685		)	(1)	2,539			(3)
	Total derivative assets	$	11,483			$	(8,771	)		$	2,712
		Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Liabilities Presented in
		Derivative				Sheet				the Balance Sheet
		Liabilities
		(in thousands)
	Derivative liabilities	$	(14,074	)		$	8,086		(2)	$	(5,988	)
	Derivatives and other noncurrent liabilities	(697		)		685			(2)	(12		)	(4)
	Total derivative liabilities	$	(14,771	)		$	8,771			$	(6,000	)
	-1	Derivative liability balances are netted against derivative asset balances with the same counterparty, and therefore are presented as a net asset in the Unaudited Consolidated Balance Sheets.
	-2	Derivative asset balances are netted against derivative liability balances with the same counterparty, and therefore are presented as a net liability in the Unaudited Consolidated Balance Sheets.
	-3	As of September 30, 2014 and December 31, 2013, this line item in the Unaudited Consolidated Balance Sheets included $16.4 million and $19.2 million of deferred financing costs and other noncurrent assets, respectively.
	-4	As of September 30, 2014 and December 31, 2013, this line item in the Unaudited Consolidated Balance Sheets included $3.0 million and $3.5 million of other noncurrent liabilities, respectively.
	The following table summarizes the cash flow hedge gains, net of tax, as of the periods indicated:
	Derivatives Qualifying as Cash Flow Hedges			Three Months Ended September 30,								Nine Months Ended September 30,
				2014				2013				2014				2013
				(in thousands)
	Amount of gain reclassified from AOCI into income (net of tax) (1)(2)	Commodity Hedges		$	219			$	1,186			$	555			$	3,688
	-1	Gains reclassified from accumulated other comprehensive income ("AOCI") into income are included in the oil, gas and NGL production revenues in the Unaudited Consolidated Statements of Operations.
	-2	Presented net of income tax expense of $0.1 million and $0.7 million for the three months ended September 30, 2014 and 2013, respectively, and $0.3 million and $2.2 million for the nine months ended September 30, 2014 and 2013, respectively.
	As of September 30, 2014, the Company had financial derivative instruments in place related to the sale of a portion of the Company's production for the following volumes for the periods indicated:
		October – December			For the year			For the  year			For the  year
		2014			2015			2016			2017
	Oil (Bbls)	975,200			4,077,500			1,554,000			182,500
	Natural gas (MMbtu)	1,762,500			7,300,000			1,830,000			—
	Natural gas liquids (Bbls)	—			—			—			—
	The table below summarizes the commodity derivative gains and losses the Company recognized related to its oil, gas and NGL derivative instruments for the periods indicated:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
		(in thousands)
	Commodity derivative gain settlements on derivatives designated as cash flow hedges (1)	$	351			$	1,899			$	889			$	5,902
	Total commodity derivative gain (loss) (2)	72,299				(25,595		)		369				(18,607		)
	-1	Included in oil, gas and NGL production revenues in the Unaudited Consolidated Statements of Operations.
	-2	Included in commodity derivative gain (loss) in the Unaudited Consolidated Statements of Operations.
	The Company's derivative financial instruments are generally executed with major financial or commodities trading institutions that expose the Company to market and credit risks and may, at times, be concentrated with certain counterparties or groups of counterparties. The Company had derivatives in place with eight different counterparties as of September 30, 2014. Although notional amounts are used to express the volume of these contracts, the amounts potentially subject to credit risk, in the event of non-performance by the counterparties, are substantially smaller. The creditworthiness of counterparties is subject to continual review by management, and the Company believes all of these institutions currently are acceptable credit risks. Full performance is anticipated, and the Company has no past due receivables from any of its counterparties.
	It is the Company's policy to enter into derivative contracts with counterparties that are lenders in the Amended Credit Facility, affiliates of lenders in the Amended Credit Facility or potential lenders in the Amended Credit Facility. The Company's derivative contracts are documented using an industry standard contract known as a Schedule to the Master Agreement and International Swaps and Derivative Association, Inc. ("ISDA") Master Agreement or other contracts. Typical terms for these contracts include credit support requirements, cross default provisions, termination events and set-off provisions. The Company is not required to provide any credit support to its counterparties other than cross collateralization with the properties securing the Amended Credit Facility. The Company has set-off provisions in its derivative contracts with lenders under its Amended Credit Facility which, in the event of a counterparty default, allow the Company to set-off amounts owed to the defaulting counterparty under the Amended Credit Facility or other obligations against monies owed the Company under derivative contracts. Where the counterparty is not a lender under the Company's Amended Credit Facility, it may not be able to set-off amounts owed by the Company under the Amended Credit Facility, even if such counterparty is an affiliate of a lender under such facility. The Company does not have any derivative balances that are offset by cash collateral.

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	The Company accounts for uncertainty in income taxes for tax positions taken or expected to be taken in a tax return in accordance with the FASB’s rules on income taxes. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained upon examination by the taxing authorities. During the three and nine months ended September 30, 2014, the Company had no uncertain tax positions.
	The Company’s policy is to classify accrued penalties and interest related to unrecognized tax benefits in the Company’s income tax provision. The Company did not record any accrued interest or penalties associated with unrecognized tax benefits during the three and nine months ended September 30, 2014 and 2013.
	Income tax benefit for the three and nine months ended September 30, 2014 and 2013 differs from the amounts that would be provided by applying the U.S. federal income tax rate to income before income taxes principally due to the effect of stock-based compensation, political lobbying expense, political contributions, nondeductible officer compensation, and other operating expenses that are not deductible for income tax purposes.

Equity_Incentive_Compensation_

Equity Incentive Compensation Plans and Other Employee Benefits	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Equity Incentive Compensation Plans and Other Employee Benefits	'
	Equity Incentive Compensation Plans and Other Employee Benefits
	The Company maintains various stock-based compensation plans and other employee benefits as discussed below. Stock-based compensation is measured at the grant date based on the value of the awards, and the fair value is recognized on a straight-line basis over the requisite service period (usually the vesting period).
	The following table presents the non-cash stock-based compensation related to equity awards for the periods indicated:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014				2013
		(in thousands)
	Common stock options	$	482		$	681		$	1,608			$	3,898
	Nonvested equity common stock	1,760			1,562			4,979				5,550
	Nonvested equity common stock units	274			277			783				989
	Nonvested performance-based equity	955			712			1,919				1,410
	Total	$	3,471		$	3,232		$	9,289			$	11,847
	Unrecognized compensation cost as of September 30, 2014 was $21.6 million related to grants of nonvested stock options and nonvested equity shares of common stock that are expected to be recognized over a weighted-average period of 2.5 years.
	Nonvested Equity Shares. The following table presents the equity awards granted pursuant to the Company's various stock compensation plans:
		Three Months Ended September 30, 2014					Three Months Ended September 30, 2013
		Number of		Weighted Average			Number of			Weighted Average
		Shares		Grant Date Fair			Shares			Grant Date Fair
				Value Per Share						Value Per Share
	Nonvested equity common stock	26,828		$	21.53		57,792			$	22.36
	Nonvested equity common stock units	850		$	22.04		2,210			$	25.11
	Nonvested performance-based equity shares	10,073		$	18.52		154,314			$	20.86
	Total shares granted	37,751					214,316
		Nine Months Ended September 30, 2014					Nine Months Ended September 30, 2013
		Number of		Weighted Average			Number of			Weighted Average
		Shares		Grant Date Fair			Shares			Grant Date Fair
				Value Per Share						Value Per Share
	Nonvested equity common stock	516,768		$	22.49		615,052			$	17.8
	Nonvested equity common stock units	44,282		$	24.98		54,429			$	22.17
	Nonvested performance-based equity shares	303,188		$	19.77		442,300			$	18.08
	Total shares granted	864,238					1,111,781
	Performance Share Programs
	2014 Program. In February 2014, the Compensation Committee approved a new performance share program (the "2014 Program") pursuant to the 2012 Equity Incentive Plan. The performance-based awards contingently vest in May 2017, depending on the level at which the performance goals are achieved. The performance goals, which will be measured over the three year period ending December 31, 2016, consist of the Company's total shareholder return ("TSR") ranking relative to a defined peer group's individual TSRs ("Relative TSR") (weighted at 60%) and the percentage change in discretionary cash flow per debt adjusted share relative to a defined peer group's percentage calculation ("DCF per Debt Adjusted Share") (weighted at 40%). The Relative TSR and DCF per Debt Adjusted Share goals will vest at 25% of the total award for performance met at the threshold level, 100% at the target level and 200% at the stretch level. If the actual results for a metric are between the threshold and target levels or between the target and stretch levels, the vested number of shares will be prorated based on the actual results compared to the threshold, target and stretch goals. If the threshold metrics are not met, no shares will vest. In any event, the total number of shares of common stock that could vest will not exceed 200% of the original number of performance shares granted. At the end of the three year vesting period, any shares that have not vested will be forfeited. All compensation expense related to the TSR metric will be recognized if the requisite service period is fulfilled, even if the market condition is not achieved. All compensation expense related to the discretionary cash flow metric will be based upon the number of shares expected to vest at the end of the three year period.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Lease Financing Obligation. The Company has a Lease Financing Obligation with Bank of America Leasing & Capital, LLC as the lead bank as discussed in Note 5. The aggregate undiscounted minimum future lease payments, including both principal and interest components, are presented below:
		As of September 30, 2014
		(in thousands)
	2014	$	134
	2015	537
	2016	537
	2017	537
	2018	537
	Thereafter	1,826
	Total	$	4,108
	Transportation Charges. The Company has entered into two firm transportation contracts to provide capacity on natural gas pipeline systems. The remaining term on these contracts is seven years. The contracts require the Company to pay transportation charges regardless of the amount of pipeline capacity utilized by the Company. These transportation costs are included in gathering, transportation and processing expense in the Unaudited Consolidated Statements of Operations. As a result of the divestitures discussed in Note 4, the Company will likely not utilize the firm capacity on the natural gas pipelines.
	The amounts in the table below represent the Company's future minimum transportation charges.
		As of September 30, 2014
		(in thousands)
	2014	$	4,577
	2015	18,692
	2016	18,692
	2017	18,692
	2018	18,692
	Thereafter	48,287
	Total	$	127,632
	Purchase Commitments. The Company has one take-or-pay purchase agreement for supply of carbon dioxide ("CO2"), which has a total financial commitment of $1.7 million. The CO2 is for use in fracture stimulation operations. Under this contract, the Company is obligated to purchase a minimum monthly volume at a set price. If the Company takes delivery of less than the minimum required amount, the Company is responsible for full payment (deficiency payment) in December 2015.
	Lease and Other Commitments. The Company leases office space, vehicles and certain equipment under non-cancelable operating leases. Additionally, the Company has entered into various long-term agreements for telecommunication services.
	The Company has entered into a sales throughput contract in the South Altamont area of the Uinta Oil Basin. Under this contract, the Company is obligated to sell and deliver a minimum volume commitment ("MVC") of 380.0 MMcf for the period of October 1, 2013 to November 30, 2014. If the minimum volume is not delivered, the Company must make a deficiency payment in the amount of up to $0.6 million. This contract replaces the initial capital expenditures associated with the connection of South Altamont wells that would otherwise be incurred as connected. As of September 30, 2014, the Company had satisfied approximately 172.5 MMcf of this commitment, resulting in an estimated deficiency payment of up to $0.3 million due December 1, 2014. Additionally, the Company has agreed to a MVC of 450.0 MMcf for the period of December 1, 2014 to November 30, 2015, with a deficiency payment of up to $0.8 million. Payment for any volume deficiency from this MVC will be due December 1, 2015.
	Future minimum annual payments under lease and other agreements are as follows:
		As of September 30, 2014
		(in thousands)
	2014	$	1,322
	2015	3,968
	2016	2,817
	2017	2,612
	2018	2,528
	Thereafter	633
	Total	$	13,880
	Litigation. The Company is subject to litigation, claims and governmental and regulatory proceedings arising in the course of ordinary business. It is the opinion of the Company's management that current claims and litigation involving the Company are not likely to have a material adverse effect on its Unaudited Consolidated Balance Sheet, Cash Flows or Statements of Operations.

Guarantor_Subsidiaries

Guarantor Subsidiaries	9 Months Ended
	Sep. 30, 2014
Text Block [Abstract]	'
Guarantor Subsidiaries	'
	Guarantor Subsidiaries
	In addition to the Amended Credit Facility, the 7.625% Senior Notes, 7.0% Senior Notes and Convertible Notes, which are registered securities, are jointly and severally guaranteed on a full and unconditional basis by the Company's 100% owned subsidiaries ("Guarantor Subsidiaries"). Presented below are the Company's unaudited condensed consolidating balance sheets, statements of operations, statements of other comprehensive income (loss) and statements of cash flows, as required by Rule 3-10 of Regulation S-X of the Securities Exchange Act of 1934, as amended.
	During the three months ended June 30, 2014, Bill Barrett Corporation, as parent, merged two of the Company's 100% owned subsidiaries, CBM Production Company and GB Acquisition Corporation, into the parent company. The unaudited condensed consolidating financial statements reflect the new guarantor structure for all periods presented.
	The following unaudited condensed consolidating financial statements have been prepared from the Company's financial information on the same basis of accounting as the Unaudited Consolidated Financial Statements. Investments in the subsidiaries are accounted for under the equity method. Accordingly, the entries necessary to consolidate the Company and the Guarantor Subsidiaries are reflected in the intercompany eliminations column.
	Condensed Consolidating Balance Sheets
		As of September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Assets:
	Current assets	$	397,890		$	52		$	—		$	397,942
	Property and equipment, net	1,636,831			79,422			—			1,716,253
	Intercompany receivable (payable)	55,634			(55,634		)	—			—
	Investment in subsidiaries	18,179			—			(18,179		)	—
	Noncurrent assets	23,089			—			—			23,089
	Total assets	$	2,131,623		$	23,840		$	(18,179	)	$	2,137,284
	Liabilities and Stockholders' Equity:
	Current liabilities	$	232,748		$	878		$	—		$	233,626
	Long-term debt	828,624			—			—			828,624
	Deferred income taxes	110,269			3,255			—			113,524
	Other noncurrent liabilities	21,038			1,528			—			22,566
	Stockholders' equity	938,944			18,179			(18,179		)	938,944
	Total liabilities and stockholders' equity	$	2,131,623		$	23,840		$	(18,179	)	$	2,137,284
		As of December 31, 2013
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Assets:
	Current assets	$	154,986		$	2,261		$	—		$	157,247
	Property and equipment, net	2,127,624			74,872			—			2,202,496
	Intercompany receivable (payable)	59,076			(59,076		)	—			—
	Investment in subsidiaries	12,063			—			(12,063		)	—
	Noncurrent assets	21,770			—			—			21,770
	Total assets	$	2,375,519		$	18,057		$	(12,063	)	$	2,381,513
	Liabilities and Stockholders' Equity:
	Current liabilities	$	192,106		$	613		$	—		$	192,719
	Long-term debt	979,082			—			—			979,082
	Deferred income taxes	158,071			3,255			—			161,326
	Other noncurrent liabilities	40,542			2,126			—			42,668
	Stockholders' equity	1,005,718			12,063			(12,063		)	1,005,718
	Total liabilities and stockholders' equity	$	2,375,519		$	18,057		$	(12,063	)	$	2,381,513
	Condensed Consolidating Statements of Operations
		Three Months Ended September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Operating and other revenues	$	128,235		$	7,028		$	—		$	135,263
	Operating expenses	(230,021		)	(5,164		)	—			(235,185		)
	General and administrative	(11,111		)	—			—			(11,111		)
	Interest income and other income (expense)	54,530			—			—			54,530
	Income (loss) before income taxes and equity in earnings of subsidiaries	(58,367		)	1,864			—			(56,503		)
	Benefit from income taxes	21,854			—			—			21,854
	Equity in earnings (loss) of subsidiaries	1,864			—			(1,864		)	—
	Net income (loss)	$	(34,649	)	$	1,864		$	(1,864	)	$	(34,649	)
		Nine Months Ended September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Operating and other revenues	$	385,703		$	19,686		$	—		$	405,389
	Operating expenses	(416,147		)	(13,605		)	—			(429,752		)
	General and administrative	(41,039		)	—			—			(41,039		)
	Interest income and other income (expense)	(51,960		)	35			—			(51,925		)
	Income (loss) before income taxes and equity in earnings of subsidiaries	(123,443		)	6,116			—			(117,327		)
Benefit from income taxes	43,343			—			—			43,343
Equity in earnings (loss) of subsidiaries	6,116			—			(6,116		)	—
Net income (loss)	$	(73,984	)	$	6,116		$	(6,116	)	$	(73,984	)
	Three Months Ended September 30, 2013
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Operating and other revenues	$	139,689		$	8,866		$	—		$	148,555
Operating expenses	(329,949		)	(4,274		)	—			(334,223		)
General and administrative	(14,402		)	—			—			(14,402		)
Interest and other income (expense)	(67,081		)	—			—			(67,081		)
Income (loss) before income taxes and equity in earnings of subsidiaries	(271,743		)	4,592			—			(267,151		)
Benefit from income taxes	100,495			—			—			100,495
Equity in earnings of subsidiaries	4,592			—			(4,592		)	—
Net income (loss)	$	(166,656	)	$	4,592		$	(4,592	)	$	(166,656	)
	Nine Months Ended September 30, 2013
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Operating and other revenues	$	407,048		$	22,083		$	—		$	429,131
Operating expenses	(556,811		)	(11,626		)	—			(568,437		)
General and administrative	(48,257		)	—			—			(48,257		)
Interest and other income (expense)	(109,290		)	—			—			(109,290		)
Income (loss) before income taxes and equity in earnings of subsidiaries	(307,310		)	10,457			—			(296,853		)
Benefit from income taxes	111,319			—			—			111,319
Equity in earnings (loss) of subsidiaries	10,457			—			(10,457		)	—
Net income (loss)	$	(185,534	)	$	10,457		$	(10,457	)	$	(185,534	)
Condensed Consolidating Statements of Comprehensive Income (Loss)
	Three Months Ended September 30, 2014
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Net income (loss)	$	(34,649	)	$	1,864		$	(1,864	)	$	(34,649	)
Other Comprehensive Loss, net of tax:
Effect of derivative financial instruments	(219		)	—			—			(219		)
Other comprehensive loss	(219		)	—			—			(219		)
Comprehensive income (loss)	$	(34,868	)	$	1,864		$	(1,864	)	$	(34,868	)
	Nine Months Ended September 30, 2014
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Net income (loss)	$	(73,984	)	$	6,116		$	(6,116	)	$	(73,984	)
Other Comprehensive Loss, net of tax:
Effect of derivative financial instruments	(555		)	—			—			(555		)
Other comprehensive loss	(555		)	—			—			(555		)
Comprehensive income (loss)	$	(74,539	)	$	6,116		$	(6,116	)	$	(74,539	)
	Three Months Ended September 30, 2013
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Net income (loss)	$	(166,656	)	$	4,592		$	(4,592	)	$	(166,656	)
Other Comprehensive Loss, net of tax:
Effect of derivative financial instruments	(1,186		)	—			—			(1,186		)
Other comprehensive loss	(1,186		)	—			—			(1,186		)
Comprehensive income (loss)	$	(167,842	)	$	4,592		$	(4,592	)	$	(167,842	)
	Nine Months Ended September 30, 2013
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Net income (loss)	$	(185,534	)	$	10,457		$	(10,457	)	$	(185,534	)
Other Comprehensive Loss, net of tax:
Effect of derivative financial instruments	(3,688		)	—			—			(3,688		)
Other comprehensive loss	(3,688		)	—			—			(3,688		)
Comprehensive income (loss)	$	(189,222	)	$	10,457		$	(10,457	)	$	(189,222	)
Condensed Consolidating Statements of Cash Flows
	Nine Months Ended September 30, 2014
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Cash flows from operating activities	$	214,521		$	16,781		$	—		$	231,302
Cash flows from investing activities:
Additions to oil and gas properties, including acquisitions	(410,417		)	(15,561		)	—			(425,978		)
Additions to furniture, fixtures and other	(2,110		)	—			—			(2,110		)
Proceeds from sale of properties and other investing activities	555,926			1,821			—			557,747
Intercompany transfers	3,041			—			(3,041		)	—
Cash flows from financing activities:
Proceeds from debt	165,000			—			—			165,000
Principal payments on debt	(283,442		)	—			—			(283,442		)
Intercompany transfers	—			(3,041		)	3,041			—
Other financing activities	(2,336		)	—			—			(2,336		)
Change in cash and cash equivalents	240,183			—			—			240,183
Beginning cash and cash equivalents	54,545			50			—			54,595
Ending cash and cash equivalents	$	294,728		$	50		$	—		$	294,778
	Nine Months Ended September 30, 2013
	Parent			Guarantor			Intercompany			Consolidated
	Issuer			Subsidiaries			Eliminations
	(in thousands)
Cash flows from operating activities	$	180,399		$	15,903		$	—		$	196,302
Cash flows from investing activities:
Additions to oil and gas properties, including acquisitions	(303,774		)	(31,823		)	—			(335,597		)
Additions to furniture, fixtures and other	(1,506		)	—			—			(1,506		)
Proceeds from sale of properties and other investing activities	784			—			—			784
Cash flows from financing activities:
Proceeds from debt	390,000			—			—			390,000
Principal payments on debt	(269,125		)	—			—			(269,125		)
Intercompany transfers	(15,920		)	15,920			—			—
Other financing activities	227			—			—			227
Change in cash and cash equivalents	(18,915		)	—			—			(18,915		)
Beginning cash and cash equivalents	79,395			50			—			79,445
Ending cash and cash equivalents	$	60,480		$	50		$	—		$	60,530

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Basis of Presentation	'
	Basis of Presentation. The accompanying Unaudited Consolidated Financial Statements include the accounts of the Company. These statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP"). All intercompany accounts and transactions have been eliminated in consolidation. In the opinion of management, the accompanying financial statements include all adjustments (consisting of normal recurring accruals and adjustments) necessary to present fairly, in all material respects, the Company's interim results. However, operating results for the periods presented are not necessarily indicative of the results that may be expected for the full year. The Company's Annual Report on Form 10-K includes certain definitions and a summary of significant accounting policies and should be read in conjunction with this Quarterly Report on Form 10-Q. Except as disclosed herein, there have been no material changes to the information disclosed in the notes to the consolidated financial statements included in the Company's 2013 Annual Report on Form 10-K.
Use of Estimates	'
	Use of Estimates. In the course of preparing the Company's financial statements in accordance with GAAP, management makes various assumptions, judgments and estimates to determine the reported amount of assets, liabilities, revenues and expenses and in the disclosure of commitments and contingencies. Changes in these assumptions, judgments and estimates will occur as a result of the passage of time and the occurrence of future events and, accordingly, actual results could differ from amounts initially established.
	Areas requiring the use of assumptions, judgments and estimates relate to the expected cash settlement of the Company's 5% Convertible Senior Notes due 2028 ("Convertible Notes") in computing diluted earnings per share, volumes of oil, natural gas and NGL reserves used in calculating depreciation, depletion and amortization ("DD&A"), the amount of expected future cash flows used in determining possible impairments of oil and gas properties and the amount of future capital costs used in these calculations. Assumptions, judgments and estimates also are required in determining asset retirement obligations, the timing of dry hole costs, impairments of undeveloped properties, valuing deferred tax assets and estimating fair values of derivative instruments and stock-based compensation awards.
Oil and Gas Properties	'
	Oil and Gas Properties. The Company's oil, gas and NGL exploration and production activities are accounted for using the successful efforts method. Under this method, all property acquisition costs and costs of exploratory and development wells are capitalized when incurred, pending determination of whether the well has found proved reserves. If an exploratory well does not find proved reserves, the costs of drilling the well are charged to expense and remain within cash flows from investing activities in the Unaudited Consolidated Statements of Cash Flows. If an exploratory well does find proved reserves, the costs remain capitalized and are included within additions to oil and gas properties and remain within cash flows from investing activities in the Unaudited Consolidated Statements of Cash Flows when incurred. The costs of development wells are capitalized whether proved reserves are added or not. Oil and gas lease acquisition costs are also capitalized. Upon sale or retirement of depreciable or depletable property, the cost and related accumulated DD&A are eliminated from the accounts and the resulting gain or loss is recognized.
	Other exploration costs, including certain geological and geophysical expenses and delay rentals for oil and gas leases, are charged to expense as incurred. The sale of a partial interest in a proved property is accounted for as a cost recovery and no gain or loss is recognized as long as this treatment does not significantly affect the unit-of-production amortization rate. Maintenance and repairs are charged to expense, and renewals and betterments are capitalized to the appropriate property and equipment accounts.
	Unproved oil and gas property costs are transferred to proved oil and gas properties if the properties are subsequently determined to be productive or are assigned proved reserves. Proceeds from sales of partial interests in unproved leases are accounted for as a recovery of cost without recognizing any gain until all costs are recovered. Unproved oil and gas properties are assessed periodically for impairment based on remaining lease terms, drilling results, reservoir performance, commodity price outlooks, future plans to develop acreage and other relevant matters.
	Materials and supplies consist primarily of tubular goods and well equipment to be used in future drilling operations or repair operations and are carried at the lower of cost or market value, on a first-in, first-out basis.
	The following table sets forth the net capitalized costs and associated accumulated DD&A and non-cash impairments relating to the Company's oil, natural gas and NGL producing activities:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Proved properties	$	382,867			$	485,427
	Wells and related equipment and facilities	1,406,678				2,192,754
	Support equipment and facilities	60,588				177,224
	Materials and supplies	13,345				8,518
	Total proved oil and gas properties	$	1,863,478			$	2,863,923
	Unproved properties	185,237				239,925
	Wells and facilities in progress	97,585				56,674
	Total unproved oil and gas properties, excluded from amortization	$	282,822			$	296,599
	Accumulated depreciation, depletion, amortization and impairment	(443,748		)		(976,339		)
	Total oil and gas properties, net	$	1,702,552			$	2,184,183
	All exploratory wells are evaluated for economic viability within one year of well completion. Exploratory wells that discover potentially economic reserves in areas where a major capital expenditure would be required before production could begin, and where the economic viability of that major capital expenditure depends upon the successful completion of further exploratory work in the area, remain capitalized if the well finds a sufficient quantity of reserves to justify its completion as a producing well and the Company is making sufficient progress assessing the reserves and the economic and operating viability of the project. As of September 30, 2014 and December 31, 2013, there were no exploratory well costs that had been capitalized for a period greater than one year since the completion of drilling.
	The Company reviews proved oil and gas properties on a field-by-field basis for impairment on a quarterly basis or whenever events and circumstances indicate that a decline in the recoverability of their carrying value may have occurred. The Company estimates the expected undiscounted future cash flows of its oil and gas properties and compares such undiscounted future cash flows to the carrying amount of the oil and gas properties to determine if the carrying amount is recoverable. If the carrying value of a property exceeds the undiscounted future cash flows, the Company will impair the carrying value to fair value based on an analysis of quantitative and qualitative factors. The Company has no guarantee that the undiscounted future cash flows analysis of its proved property represents the applicable market value. The factors used to determine fair value include, but are not limited to, recent sales prices of comparable properties, the present value of future revenues, net of estimated operating and development costs using estimates of reserves, future commodity pricing, future production estimates, anticipated capital expenditures and various discount rates commensurate with the risk and current market conditions associated with realizing the expected cash flows projected.
	The Company recognized non-cash impairment charges, which were included within impairment, dry hole costs and abandonment expense in the Unaudited Consolidated Statements of Operations, as follows:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
		(in thousands)
	Non-cash impairment of proved oil and gas properties	$	11,493		(1)	$	198,787		(2)	$	12,531		(3)	$	198,787		(2)
	Non-cash impairment of unproved oil and gas properties	15,250			(1)	17,777			(2)	15,250			(3)	17,777			(2)
	Non-cash impairment of inventory	—				—				340				—
	Dry hole costs	3				(36		)		96				928
	Abandonment expense	2,363				2,835				4,396				10,154
	Total non-cash impairment, dry hole costs and abandonment expense	$	29,109			$	219,363			$	32,613			$	227,646
	-1	As a result of the Powder River Oil Divestiture (see Note 4) and results of drilling and completion activity in the Paradox Basin during the three months ended September 30, 2014, the remaining carrying values of Powder River Oil and Paradox Basin assets were analyzed relative to their estimated fair market values. As a result, the Company recognized proved and unproved property impairments of $11.5 million and $15.3 million, respectively.
	-2	We classified certain oil and gas properties in the West Tavaputs field in the Uinta Basin as held for sale as of September 30, 2013 (see Note 4). Upon the classification as held for sale, the carrying value of the related properties was analyzed relative to the estimated fair value. As a result, we recognized $198.8 million of proved impairment expense and $2.5 million of unproved property impairment expense during the three and nine months ended September 30, 2013. In addition, we recognized $15.3 million of impairment expense related to certain unproved oil and gas properties within various exploration and development projects primarily as a result of no future plans to evaluate the remaining acreage and an estimated market value below our carrying value.
	-3	As a result of the Powder River Oil Divestiture and results of drilling and completion activity in the Paradox Basin during the nine months ended September 30, 2014, the remaining carrying values of Powder River Oil and Paradox Basin assets were analyzed relative to their estimated fair market values. As a result, the Company recognized proved and unproved property impairments of $11.5 million and $15.3 million, respectively. In addition, $1.0 million of proved impairment expense was incurred during the nine months ended September 30, 2014 related to the West Tavaputs Divestiture (see Note 4) based upon a true up of previously estimated fair value relative to carrying value.
	The provision for DD&A of oil and gas properties is calculated on a field-by-field basis using the unit-of-production method. Natural gas and NGLs are converted to an oil equivalent, Boe, at the standard rate of six Mcf to one Boe and forty-two gallons to one Boe, respectively. Estimated future dismantlement, restoration and abandonment costs are taken into consideration by this calculation
Accounts Payable and Accrued Liabilities	'
	Accounts Payable and Accrued Liabilities. Accounts payable and accrued liabilities are comprised of the following:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Accrued drilling, completion and facility costs	$	85,517			$	54,750
	Accrued lease operating, gathering, transportation and processing expenses	13,025				17,317
	Accrued general and administrative expenses	7,042				14,605
	Trade payables and other	49,336				29,256
	Total accounts payable and accrued liabilities	$	154,920			$	115,928
Environmental Liabilities	'
	Environmental Liabilities. Environmental expenditures that relate to an existing condition caused by past operations and that do not contribute to current or future revenue generation are expensed. Environmental liabilities are accrued when environmental assessments and/or clean-ups are probable, and the costs can be reasonably estimated.
Revenue Recognition	'
	Revenue Recognition. Oil, gas and NGL revenues are recognized when production is sold to a purchaser at a fixed or determinable price, when delivery has occurred and title has transferred, and collectability of the revenue is reasonably assured. The Company uses the sales method to account for gas and NGL imbalances. Under this method, revenues are recorded on the basis of gas and NGLs actually sold by the Company. In addition, the Company records revenues for its share of gas and NGLs sold by other owners that cannot be volumetrically balanced in the future due to insufficient remaining reserves. The Company also reduces revenues for other owners' gas and NGLs sold by the Company that cannot be volumetrically balanced in the future due to insufficient remaining reserves. The Company's remaining over- and under- produced gas and NGLs balancing positions are taken into account in determining the Company's proved oil, gas and NGL reserves. Imbalances at September 30, 2014 and 2013 were not material.
Derivative Instruments and Hedging Activities	'
	Derivative Instruments and Hedging Activities. The Company periodically uses derivative financial instruments to achieve a more predictable cash flow from its oil, natural gas and NGL sales by reducing its exposure to price fluctuations. Derivative instruments are recorded at fair market value and are included in the Unaudited Consolidated Balance Sheets as assets or liabilities.
Income Taxes	'
	Income Taxes. Income taxes are provided for the tax effects of transactions reported in the financial statements and consist of taxes currently payable plus deferred income taxes related to certain income and expenses recognized in different periods for financial and income tax reporting purposes. Deferred income tax assets and liabilities represent the future tax return consequences of those differences, which will either be taxable or deductible when assets are recovered or liabilities are settled. Deferred income taxes also include tax credits and net operating losses that are available to offset future income taxes. Deferred income taxes are measured by applying currently enacted tax rates.
	The Company accounts for uncertainty in income taxes for tax positions taken or expected to be taken in a tax return. Only tax positions that meet the more-likely-than-not recognition threshold are recognized.
Earnings/Loss Per Share	'
	Earnings/Loss Per Share. Basic net income (loss) per common share is calculated by dividing net income (loss) attributable to common stock by the weighted average number of common shares outstanding during each period. Diluted net income per common share is calculated by dividing net income attributable to common stock by the weighted average number of common shares outstanding and other dilutive securities. Potentially dilutive securities for the diluted net income per common share calculations consist of nonvested equity shares of common stock, in-the-money outstanding stock options to purchase the Company's common stock and shares into which the Convertible Notes are convertible. No potential common shares are included in the computation of any diluted per share amount when a net loss exists, as was the case for the three and nine months ended September 30, 2014 and 2013.
	In satisfaction of its obligation upon conversion of the Convertible Notes, the Company may elect to deliver, at its option, cash, shares of its common stock or a combination of cash and shares of its common stock. As of September 30, 2014, the Company expected to settle the remaining Convertible Notes in cash. Therefore, the treasury stock method was used to measure the potentially dilutive impact of shares associated with that remaining conversion feature. The Company has the right with at least 30 days' notice to call the Convertible Notes and the holders have the right to require the Company to purchase the notes on March 20, 2015. The Convertible Notes have not been dilutive since their issuance in March 2008 and, therefore, did not impact the diluted net income (loss) per common share calculation for the three and nine months ended September 30, 2014 and 2013. The diluted net income (loss) per common share excludes the anti-dilutive effect of 1,336,252 and 2,450,539 shares of stock options and nonvested performance-based shares of common stock for the three months ended September 30, 2014 and 2013, and 1,199,451 and 2,731,578 shares of stock options and nonvested performance-based shares of common stock for the nine months ended September 30, 2014 and 2013, respectively.
	The following table sets forth the calculation of basic and diluted loss per share:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
		(in thousands, except per share amounts)
	Net loss	$	(34,649	)		$	(166,656	)		$	(73,984	)		$	(185,534	)
	Basic weighted-average common shares outstanding in period	48,060				47,535				47,983				47,453
	Add dilutive effects of stock options and nonvested equity shares of common stock	—				—				—				—
	Diluted weighted-average common shares outstanding in period	48,060				47,535				47,983				47,453
	Basic net loss per common share	$	(0.72	)		$	(3.51	)		$	(1.54	)		$	(3.91	)
	Diluted net loss per common share	$	(0.72	)		$	(3.51	)		$	(1.54	)		$	(3.91	)
New Accounting Pronouncements	'
	New Accounting Pronouncements. In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers. The objective of this update is to clarify the principles for recognizing revenue and to develop a common revenue standard. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. The Company is currently evaluating the potential impact that the adoption will have on the Company’s disclosures and financial statements.
	In June 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. The objective of this update is to provide guidance on the treatment of a performance target that could be achieved after the requisite service period. ASU 2014-12 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. The adoption of this standard will not have an impact on the Company's consolidated financial statements.
	In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern. The objective of this update is to provide guidance in GAAP about management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern and to provide related footnote disclosures. ASU 2014-15 is effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. The adoption of this standard will not have an impact on the Company's consolidated financial statements.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Summary of Accounts Receivable	'
	Accounts receivable is comprised of the following:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Accrued oil, gas and NGL sales	$	58,175			$	67,583
	Due from joint interest owners	25,339				23,507
	Other	5,054				6,517
	Allowance for doubtful accounts	(14		)		(21		)
	Total accounts receivable	$	88,554			$	97,586
Net Capitalized Costs and Associated Accumulated DD&A and Non Cash Impairments	'
	The following table sets forth the net capitalized costs and associated accumulated DD&A and non-cash impairments relating to the Company's oil, natural gas and NGL producing activities:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Proved properties	$	382,867			$	485,427
	Wells and related equipment and facilities	1,406,678				2,192,754
	Support equipment and facilities	60,588				177,224
	Materials and supplies	13,345				8,518
	Total proved oil and gas properties	$	1,863,478			$	2,863,923
	Unproved properties	185,237				239,925
	Wells and facilities in progress	97,585				56,674
	Total unproved oil and gas properties, excluded from amortization	$	282,822			$	296,599
	Accumulated depreciation, depletion, amortization and impairment	(443,748		)		(976,339		)
	Total oil and gas properties, net	$	1,702,552			$	2,184,183
Non-Cash Impairment Charges, Included within Impairment, Dry Hole Costs and Abandonment Expense in Consolidated Statements of Operations	'
	The Company recognized non-cash impairment charges, which were included within impairment, dry hole costs and abandonment expense in the Unaudited Consolidated Statements of Operations, as follows:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
		(in thousands)
	Non-cash impairment of proved oil and gas properties	$	11,493		(1)	$	198,787		(2)	$	12,531		(3)	$	198,787		(2)
	Non-cash impairment of unproved oil and gas properties	15,250			(1)	17,777			(2)	15,250			(3)	17,777			(2)
	Non-cash impairment of inventory	—				—				340				—
	Dry hole costs	3				(36		)		96				928
	Abandonment expense	2,363				2,835				4,396				10,154
	Total non-cash impairment, dry hole costs and abandonment expense	$	29,109			$	219,363			$	32,613			$	227,646
	-1	As a result of the Powder River Oil Divestiture (see Note 4) and results of drilling and completion activity in the Paradox Basin during the three months ended September 30, 2014, the remaining carrying values of Powder River Oil and Paradox Basin assets were analyzed relative to their estimated fair market values. As a result, the Company recognized proved and unproved property impairments of $11.5 million and $15.3 million, respectively.
	-2	We classified certain oil and gas properties in the West Tavaputs field in the Uinta Basin as held for sale as of September 30, 2013 (see Note 4). Upon the classification as held for sale, the carrying value of the related properties was analyzed relative to the estimated fair value. As a result, we recognized $198.8 million of proved impairment expense and $2.5 million of unproved property impairment expense during the three and nine months ended September 30, 2013. In addition, we recognized $15.3 million of impairment expense related to certain unproved oil and gas properties within various exploration and development projects primarily as a result of no future plans to evaluate the remaining acreage and an estimated market value below our carrying value.
	-3	As a result of the Powder River Oil Divestiture and results of drilling and completion activity in the Paradox Basin during the nine months ended September 30, 2014, the remaining carrying values of Powder River Oil and Paradox Basin assets were analyzed relative to their estimated fair market values. As a result, the Company recognized proved and unproved property impairments of $11.5 million and $15.3 million, respectively. In addition, $1.0 million of proved impairment expense was incurred during the nine months ended September 30, 2014 related to the West Tavaputs Divestiture (see Note 4) based upon a true up of previously estimated fair value relative to carrying value.
Accounts Payable and Accrued Liabilities	'
	Accounts payable and accrued liabilities are comprised of the following:
		As of September 30, 2014				As of December 31, 2013
		(in thousands)
	Accrued drilling, completion and facility costs	$	85,517			$	54,750
	Accrued lease operating, gathering, transportation and processing expenses	13,025				17,317
	Accrued general and administrative expenses	7,042				14,605
	Trade payables and other	49,336				29,256
	Total accounts payable and accrued liabilities	$	154,920			$	115,928
Calculation of Basic and Diluted Earnings (Loss) Per Share	'
	The following table sets forth the calculation of basic and diluted loss per share:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
		(in thousands, except per share amounts)
	Net loss	$	(34,649	)		$	(166,656	)		$	(73,984	)		$	(185,534	)
	Basic weighted-average common shares outstanding in period	48,060				47,535				47,983				47,453
	Add dilutive effects of stock options and nonvested equity shares of common stock	—				—				—				—
	Diluted weighted-average common shares outstanding in period	48,060				47,535				47,983				47,453
	Basic net loss per common share	$	(0.72	)		$	(3.51	)		$	(1.54	)		$	(3.91	)
	Diluted net loss per common share	$	(0.72	)		$	(3.51	)		$	(1.54	)		$	(3.91	)

Supplemental_Disclosures_of_Ca1

Supplemental Disclosures of Cash Flow Information (Tables)	9 Months Ended
	Sep. 30, 2014
Supplemental Cash Flow Elements [Abstract]	'
Supplemental Cash Flow Information	'
	Supplemental cash flow information is as follows:
		Nine Months Ended September 30,
		2014			2013
		(in thousands)
	Cash paid for interest	$	36,267		$	61,796
	Cash paid for income taxes	1			1,861
	Supplemental disclosures of non-cash investing and financing activities:
	Current liabilities	90,381			75,265
	Net increase (decrease) in asset retirement obligations	(23,327		)	2,924
	Retirement of treasury stock	(2,462		)	(1,415		)
	Fair value of properties exchanged in non-cash transactions	77,078			—
	Relief from lease financing obligation	36,106			45,190

Divestitures_Divestitures_Tabl

Divestitures Divestitures (Tables)	9 Months Ended
	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Table Text Block]	'
	The carrying amounts by major asset class within the disposal group for the Piceance Divestiture are summarized below (in thousands):
	Assets:
	Proved properties	$	1,320,757
	Furniture, equipment and other	4,907
	Accumulated depreciation, depletion, amortization and impairment	(688,864		)
	Other assets	173
	Total assets	$	636,973
	Liabilities:
	Asset retirement obligation	$	22,448
	Lease financing obligation	36,106
	Total liabilities	$	58,554
	Net assets	$	578,419

LongTerm_Debt_Tables

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Outstanding Debt	'
	The Company's outstanding debt is summarized below:
			As of September 30, 2014									As of December 31, 2013
		Maturity Date	Principal			Unamortized			Carrying			Principal		Unamortized		Carrying
						Discount			Amount					Discount		Amount
			(in thousands)
	Amended Credit Facility (1)	October 31, 2016	$	—		$	—		$	—		$	115,000	$	—	$	115,000
	Convertible Notes (2)	March 15, 2028 (3)	25,344			—			25,344			25,344		—		25,344
	7.625% Senior Notes (4)	October 1, 2019	400,000			—			400,000			400,000		—		400,000
	7.0% Senior Notes (5)	October 15, 2022	400,000			—			400,000			400,000		—		400,000
	Lease Financing Obligation (6)	August 10, 2020	3,721			—			3,721			43,329		—		43,329
	Total Debt		$	829,065		$	—		$	829,065		$	983,673	$	—	$	983,673
	Less: Current Portion of Long-Term Debt		441			—			441			4,591		—		4,591
	Total Long-Term Debt		$	828,624		$	—		$	828,624		$	979,082	$	—	$	979,082
	-1	The recorded value of the Amended Credit Facility approximates its fair value due to its floating rate structure.
	-2	The aggregate estimated fair value of the Convertible Notes was approximately $25.4 million and $25.1 million as of September 30, 2014 and December 31, 2013, respectively, based on reported market trades of these instruments.
	-3	The Company has the right at any time, with at least 30 days' notice, to call the Convertible Notes, and the holders have the right to require the Company to purchase the notes on each of March 20, 2015, March 20, 2018 and March 20, 2023.
	-4	The aggregate estimated fair value of the 7.625% Senior Notes was approximately $407.3 million and $430.2 million as of September 30, 2014 and December 31, 2013, respectively, based on reported market trades of these instruments.
	-5	The aggregate estimated fair value of the 7.0% Senior Notes was approximately $416.0 million and $417.0 million as of September 30, 2014 and December 31, 2013, respectively, based on reported market trades of these instruments.
	-6	The aggregate estimated fair value of the Lease Financing Obligation was approximately $3.5 million as of September 30, 2014, and $41.7 million as of December 31, 2013. The decrease in estimated fair value is primarily related to the sale of equipment in the West Tavaputs and Piceance Divestitures. Because there is no active, public market for the Lease Financing Obligation, the aggregate estimated fair value was based on market-based parameters of comparable term secured financing instruments.
Cash and Non-Cash Portion of Interest Expense Related to Long Term Debt	'
	The following table summarizes, for the periods indicated, the cash or accrued portion of interest expense related to the Amended Credit Facility, the 9.875% Senior Notes that were redeemed in full on July 15, 2013, Convertible Notes, 7.625% Senior Notes, 7.0% Senior Notes and the Lease Financing Obligation along with the non-cash portion resulting from the amortization of the debt discount and transaction costs through interest expense:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
		(in thousands)
	Amended Credit Facility (1)
	Cash interest	$	1,771		$	2,296		$	4,392		$	4,211
	Non-cash interest	$	586		$	585		$	1,757		$	1,756
	9.875% Senior Notes (2)
	Cash interest	$	—		$	1,029		$	—		$	13,373
	Non-cash interest	$	—		$	—		$	—		$	1,361
	Convertible Notes (3)
	Cash interest	$	306		$	310		$	940		$	943
	Non-cash interest	$	1		$	1		$	4		$	4
	7.625% Senior Notes (4)
	Cash interest	$	7,625		$	7,625		$	22,875		$	22,875
	Non-cash interest	$	273		$	272		$	817		$	798
	7.0% Senior Notes (5)
	Cash interest	$	7,000		$	7,000		$	21,000		$	21,000
	Non-cash interest	$	204		$	203		$	610		$	592
	Lease Financing Obligation (6)
	Cash interest	$	248		$	750		$	765		$	2,305
	Non-cash interest	$	3		$	8		$	11		$	24
	-1	Cash interest includes amounts related to interest and commitment fees paid on the Amended Credit Facility and participation and fronting fees paid on the letter of credit.
	-2	The stated interest rate for the 9.875% Senior Notes was 9.875% per annum with an effective interest rate of 11.2% per annum. The Company redeemed the 9.875% Senior Notes in full on July 15, 2013.
	-3	The stated interest rate for the Convertible Notes is 5% per annum. The effective interest rate of the Convertible Notes includes amortization of the debt discount, which represented the fair value of the equity conversion feature at the time of issue. The stated interest rate of 5% on the Convertible Notes will be the effective interest rate of the $25.3 million remaining principal balance, as the related debt discount was fully amortized as of March 31, 2012.
	-4	The stated interest rate for the 7.625% Senior Notes is 7.625% per annum with an effective interest rate of 8.0% per annum.
	-5	The stated interest rate for the 7.0% Senior Notes is 7.0% per annum with an effective interest rate of 7.2% per annum.
	-6	The effective interest rate for the Lease Financing Obligation is 3.3% per annum. The decrease in cash interest from $0.8 million to $0.2 million for the three months ended September 30, 2013 and September 30, 2014, respectively, and from $2.3 million to $0.8 million for the nine months ended September 30, 2013 and September 30, 2014, respectively, is due to the West Tavaputs Divestiture. The purchaser assumed approximately 51% of the Lease Financing Obligation, including the buyout option, related to West Tavaputs equipment.

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	9 Months Ended
	Sep. 30, 2014
Asset Retirement Obligation Disclosure [Abstract]	'
Schedule of Asset Retirement Obligations	'
	A reconciliation of the Company's asset retirement obligations for the nine months ended September 30, 2014 is as follows (in thousands):
	As of December 31, 2013	$	43,005
	Liabilities incurred	3,627
	Liabilities settled	(4,383		)
	Disposition of properties	(23,722		)
	Accretion expense	2,532
	Revisions to estimate	1,151
	As of September 30, 2014	$	22,210
	Less: Current asset retirement obligations	2,641
	Long-term asset retirement obligations	$	19,569

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value, Balance Sheet Grouping	'
	The following tables set forth by level within the fair value hierarchy the Company's financial assets and financial liabilities that were measured at fair value on a recurring basis. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company's assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of assets and liabilities and their placement within the fair value hierarchy levels.
		As of September 30, 2014
		Level 1		Level 2		Level 3		Total
		(in thousands)
	Assets
	Deferred Compensation Plan	$	914	$	—	$	—	$	914
	Cash Equivalents - Money Market Funds	53		—		—		53
	Commodity Derivatives	—		20,530		—		20,530
	Liabilities
	Commodity Derivatives	$	—	$	2,757	$	—	$	2,757
		As of December 31, 2013
		Level 1		Level 2		Level 3		Total
		(in thousands)
	Assets
	Deferred Compensation Plan	$	941	$	—	$	—	$	941
	Cash Equivalents - Money Market Funds	53		—		—		53
	Commodity Derivatives	—		11,483		—		11,483
	Liabilities
	Commodity Derivatives	$	—	$	14,771	$	—	$	14,771

Derivative_Instruments_Tables

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Fair Value Amounts of Derivative Instruments	'
	The following table summarizes the location, as well as the gross and net fair value amounts of all derivative instruments presented in the Unaudited Consolidated Balance Sheets as of the dates indicated.
		As of September 30, 2014
	Balance Sheet	Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Assets Presented in the
		Derivative Assets				Sheet				Balance Sheet
		(in thousands)
	Derivative assets	$	13,623			$	(2,528	)	(1)	$	11,095
	Deferred financing costs and other noncurrent assets	6,907				(229		)	(1)	6,678			(3)
	Total derivative assets	$	20,530			$	(2,757	)		$	17,773
		Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Liabilities Presented in
		Derivative				Sheet				the Balance Sheet
		Liabilities
		(in thousands)
	Derivative liabilities	$	(2,528	)		$	2,528		(2)	$	—
	Derivatives and other noncurrent liabilities	(229		)		229			(2)	—			(4)
	Total derivative liabilities	$	(2,757	)		$	2,757			$	—
		As of December 31, 2013
	Balance Sheet	Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Assets Presented in the
		Derivative Assets				Sheet				Balance Sheet
		(in thousands)
	Derivative assets	$	8,259			$	(8,086	)	(1)	$	173
	Deferred financing costs and other noncurrent assets	3,224				(685		)	(1)	2,539			(3)
	Total derivative assets	$	11,483			$	(8,771	)		$	2,712
		Gross Amounts of				Gross Amounts				Net Amounts of Derivative
		Recognized				Offset in the Balance				Liabilities Presented in
		Derivative				Sheet				the Balance Sheet
		Liabilities
		(in thousands)
	Derivative liabilities	$	(14,074	)		$	8,086		(2)	$	(5,988	)
	Derivatives and other noncurrent liabilities	(697		)		685			(2)	(12		)	(4)
	Total derivative liabilities	$	(14,771	)		$	8,771			$	(6,000	)
	-1	Derivative liability balances are netted against derivative asset balances with the same counterparty, and therefore are presented as a net asset in the Unaudited Consolidated Balance Sheets.
	-2	Derivative asset balances are netted against derivative liability balances with the same counterparty, and therefore are presented as a net liability in the Unaudited Consolidated Balance Sheets.
	-3	As of September 30, 2014 and December 31, 2013, this line item in the Unaudited Consolidated Balance Sheets included $16.4 million and $19.2 million of deferred financing costs and other noncurrent assets, respectively.
	-4	As of September 30, 2014 and December 31, 2013, this line item in the Unaudited Consolidated Balance Sheets included $3.0 million and $3.5 million of other noncurrent liabilities, respectively.
Cash Flow Hedge Gains and Losses	'
	The following table summarizes the cash flow hedge gains, net of tax, as of the periods indicated:
	Derivatives Qualifying as Cash Flow Hedges			Three Months Ended September 30,								Nine Months Ended September 30,
				2014				2013				2014				2013
				(in thousands)
	Amount of gain reclassified from AOCI into income (net of tax) (1)(2)	Commodity Hedges		$	219			$	1,186			$	555			$	3,688
	-1	Gains reclassified from accumulated other comprehensive income ("AOCI") into income are included in the oil, gas and NGL production revenues in the Unaudited Consolidated Statements of Operations.
	-2	Presented net of income tax expense of $0.1 million and $0.7 million for the three months ended September 30, 2014 and 2013, respectively, and $0.3 million and $2.2 million for the nine months ended September 30, 2014 and 2013, respectively.
Financial Instruments for Hedging Volumes	'
	As of September 30, 2014, the Company had financial derivative instruments in place related to the sale of a portion of the Company's production for the following volumes for the periods indicated:
		October – December			For the year			For the  year			For the  year
		2014			2015			2016			2017
	Oil (Bbls)	975,200			4,077,500			1,554,000			182,500
	Natural gas (MMbtu)	1,762,500			7,300,000			1,830,000			—
	Natural gas liquids (Bbls)	—			—			—			—
Realized and Unrealized Gains and Losses on Commodity Derivative Instruments	'
	The table below summarizes the commodity derivative gains and losses the Company recognized related to its oil, gas and NGL derivative instruments for the periods indicated:
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014				2013				2014				2013
		(in thousands)
	Commodity derivative gain settlements on derivatives designated as cash flow hedges (1)	$	351			$	1,899			$	889			$	5,902
	Total commodity derivative gain (loss) (2)	72,299				(25,595		)		369				(18,607		)
	-1	Included in oil, gas and NGL production revenues in the Unaudited Consolidated Statements of Operations.
	-2	Included in commodity derivative gain (loss) in the Unaudited Consolidated Statements of Operations.

Equity_Incentive_Compensation_1

Equity Incentive Compensation Plans and Other Employee Benefits (Tables)	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Non-Cash Stock-Based Compensation Cost Related to Equity Awards	'
	The following table presents the non-cash stock-based compensation related to equity awards for the periods indicated:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014				2013
		(in thousands)
	Common stock options	$	482		$	681		$	1,608			$	3,898
	Nonvested equity common stock	1,760			1,562			4,979				5,550
	Nonvested equity common stock units	274			277			783				989
	Nonvested performance-based equity	955			712			1,919				1,410
	Total	$	3,471		$	3,232		$	9,289			$	11,847
Stock Options and Nonvested Equity Shares, Equity Awards Granted	'
	The following table presents the equity awards granted pursuant to the Company's various stock compensation plans:
		Three Months Ended September 30, 2014					Three Months Ended September 30, 2013
		Number of		Weighted Average			Number of			Weighted Average
		Shares		Grant Date Fair			Shares			Grant Date Fair
				Value Per Share						Value Per Share
	Nonvested equity common stock	26,828		$	21.53		57,792			$	22.36
	Nonvested equity common stock units	850		$	22.04		2,210			$	25.11
	Nonvested performance-based equity shares	10,073		$	18.52		154,314			$	20.86
	Total shares granted	37,751					214,316
		Nine Months Ended September 30, 2014					Nine Months Ended September 30, 2013
		Number of		Weighted Average			Number of			Weighted Average
		Shares		Grant Date Fair			Shares			Grant Date Fair
				Value Per Share						Value Per Share
	Nonvested equity common stock	516,768		$	22.49		615,052			$	17.8
	Nonvested equity common stock units	44,282		$	24.98		54,429			$	22.17
	Nonvested performance-based equity shares	303,188		$	19.77		442,300			$	18.08
	Total shares granted	864,238					1,111,781

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Aggregate Undiscounted Minimum Future Lease Payments	'
	The Company has a Lease Financing Obligation with Bank of America Leasing & Capital, LLC as the lead bank as discussed in Note 5. The aggregate undiscounted minimum future lease payments, including both principal and interest components, are presented below:
		As of September 30, 2014
		(in thousands)
	2014	$	134
	2015	537
	2016	537
	2017	537
	2018	537
	Thereafter	1,826
	Total	$	4,108
Gross Future Minimum Transportation Demand and Firm Processing Charges	'
	The amounts in the table below represent the Company's future minimum transportation charges.
		As of September 30, 2014
		(in thousands)
	2014	$	4,577
	2015	18,692
	2016	18,692
	2017	18,692
	2018	18,692
	Thereafter	48,287
	Total	$	127,632
Future Minimum Annual Payments Under Drilling, Lease and Other Agreements	'
	Future minimum annual payments under lease and other agreements are as follows:
		As of September 30, 2014
		(in thousands)
	2014	$	1,322
	2015	3,968
	2016	2,817
	2017	2,612
	2018	2,528
	Thereafter	633
	Total	$	13,880

Guarantor_Subsidiaries_Tables

Guarantor Subsidiaries (Tables)	9 Months Ended
	Sep. 30, 2014
Text Block [Abstract]	'
Schedule of Condensed Consolidating Balance Sheets	'
	Condensed Consolidating Balance Sheets
		As of September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Assets:
	Current assets	$	397,890		$	52		$	—		$	397,942
	Property and equipment, net	1,636,831			79,422			—			1,716,253
	Intercompany receivable (payable)	55,634			(55,634		)	—			—
	Investment in subsidiaries	18,179			—			(18,179		)	—
	Noncurrent assets	23,089			—			—			23,089
	Total assets	$	2,131,623		$	23,840		$	(18,179	)	$	2,137,284
	Liabilities and Stockholders' Equity:
	Current liabilities	$	232,748		$	878		$	—		$	233,626
	Long-term debt	828,624			—			—			828,624
	Deferred income taxes	110,269			3,255			—			113,524
	Other noncurrent liabilities	21,038			1,528			—			22,566
	Stockholders' equity	938,944			18,179			(18,179		)	938,944
	Total liabilities and stockholders' equity	$	2,131,623		$	23,840		$	(18,179	)	$	2,137,284
		As of December 31, 2013
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Assets:
	Current assets	$	154,986		$	2,261		$	—		$	157,247
	Property and equipment, net	2,127,624			74,872			—			2,202,496
	Intercompany receivable (payable)	59,076			(59,076		)	—			—
	Investment in subsidiaries	12,063			—			(12,063		)	—
	Noncurrent assets	21,770			—			—			21,770
	Total assets	$	2,375,519		$	18,057		$	(12,063	)	$	2,381,513
	Liabilities and Stockholders' Equity:
	Current liabilities	$	192,106		$	613		$	—		$	192,719
	Long-term debt	979,082			—			—			979,082
	Deferred income taxes	158,071			3,255			—			161,326
	Other noncurrent liabilities	40,542			2,126			—			42,668
	Stockholders' equity	1,005,718			12,063			(12,063		)	1,005,718
	Total liabilities and stockholders' equity	$	2,375,519		$	18,057		$	(12,063	)	$	2,381,513
Schedule of Condensed Consolidating Statements of Operations	'
	Condensed Consolidating Statements of Operations
		Three Months Ended September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Operating and other revenues	$	128,235		$	7,028		$	—		$	135,263
	Operating expenses	(230,021		)	(5,164		)	—			(235,185		)
	General and administrative	(11,111		)	—			—			(11,111		)
	Interest income and other income (expense)	54,530			—			—			54,530
	Income (loss) before income taxes and equity in earnings of subsidiaries	(58,367		)	1,864			—			(56,503		)
	Benefit from income taxes	21,854			—			—			21,854
	Equity in earnings (loss) of subsidiaries	1,864			—			(1,864		)	—
	Net income (loss)	$	(34,649	)	$	1,864		$	(1,864	)	$	(34,649	)
		Nine Months Ended September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Operating and other revenues	$	385,703		$	19,686		$	—		$	405,389
	Operating expenses	(416,147		)	(13,605		)	—			(429,752		)
	General and administrative	(41,039		)	—			—			(41,039		)
	Interest income and other income (expense)	(51,960		)	35			—			(51,925		)
	Income (loss) before income taxes and equity in earnings of subsidiaries	(123,443		)	6,116			—			(117,327		)
	Benefit from income taxes	43,343			—			—			43,343
	Equity in earnings (loss) of subsidiaries	6,116			—			(6,116		)	—
	Net income (loss)	$	(73,984	)	$	6,116		$	(6,116	)	$	(73,984	)
		Three Months Ended September 30, 2013
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Operating and other revenues	$	139,689		$	8,866		$	—		$	148,555
	Operating expenses	(329,949		)	(4,274		)	—			(334,223		)
	General and administrative	(14,402		)	—			—			(14,402		)
	Interest and other income (expense)	(67,081		)	—			—			(67,081		)
	Income (loss) before income taxes and equity in earnings of subsidiaries	(271,743		)	4,592			—			(267,151		)
	Benefit from income taxes	100,495			—			—			100,495
	Equity in earnings of subsidiaries	4,592			—			(4,592		)	—
	Net income (loss)	$	(166,656	)	$	4,592		$	(4,592	)	$	(166,656	)
		Nine Months Ended September 30, 2013
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Operating and other revenues	$	407,048		$	22,083		$	—		$	429,131
	Operating expenses	(556,811		)	(11,626		)	—			(568,437		)
	General and administrative	(48,257		)	—			—			(48,257		)
	Interest and other income (expense)	(109,290		)	—			—			(109,290		)
	Income (loss) before income taxes and equity in earnings of subsidiaries	(307,310		)	10,457			—			(296,853		)
	Benefit from income taxes	111,319			—			—			111,319
	Equity in earnings (loss) of subsidiaries	10,457			—			(10,457		)	—
	Net income (loss)	$	(185,534	)	$	10,457		$	(10,457	)	$	(185,534	)
Schedule of Condensed Consolidating Statements of Comprehensive Income (Loss)	'
	Condensed Consolidating Statements of Comprehensive Income (Loss)
		Three Months Ended September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Net income (loss)	$	(34,649	)	$	1,864		$	(1,864	)	$	(34,649	)
	Other Comprehensive Loss, net of tax:
	Effect of derivative financial instruments	(219		)	—			—			(219		)
	Other comprehensive loss	(219		)	—			—			(219		)
	Comprehensive income (loss)	$	(34,868	)	$	1,864		$	(1,864	)	$	(34,868	)
		Nine Months Ended September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Net income (loss)	$	(73,984	)	$	6,116		$	(6,116	)	$	(73,984	)
	Other Comprehensive Loss, net of tax:
	Effect of derivative financial instruments	(555		)	—			—			(555		)
	Other comprehensive loss	(555		)	—			—			(555		)
	Comprehensive income (loss)	$	(74,539	)	$	6,116		$	(6,116	)	$	(74,539	)
		Three Months Ended September 30, 2013
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Net income (loss)	$	(166,656	)	$	4,592		$	(4,592	)	$	(166,656	)
	Other Comprehensive Loss, net of tax:
	Effect of derivative financial instruments	(1,186		)	—			—			(1,186		)
	Other comprehensive loss	(1,186		)	—			—			(1,186		)
	Comprehensive income (loss)	$	(167,842	)	$	4,592		$	(4,592	)	$	(167,842	)
		Nine Months Ended September 30, 2013
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Net income (loss)	$	(185,534	)	$	10,457		$	(10,457	)	$	(185,534	)
	Other Comprehensive Loss, net of tax:
	Effect of derivative financial instruments	(3,688		)	—			—			(3,688		)
	Other comprehensive loss	(3,688		)	—			—			(3,688		)
	Comprehensive income (loss)	$	(189,222	)	$	10,457		$	(10,457	)	$	(189,222	)
Schedule of Condensed Consolidating Statements of Cash Flows	'
	Condensed Consolidating Statements of Cash Flows
		Nine Months Ended September 30, 2014
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Cash flows from operating activities	$	214,521		$	16,781		$	—		$	231,302
	Cash flows from investing activities:
	Additions to oil and gas properties, including acquisitions	(410,417		)	(15,561		)	—			(425,978		)
	Additions to furniture, fixtures and other	(2,110		)	—			—			(2,110		)
	Proceeds from sale of properties and other investing activities	555,926			1,821			—			557,747
	Intercompany transfers	3,041			—			(3,041		)	—
	Cash flows from financing activities:
	Proceeds from debt	165,000			—			—			165,000
	Principal payments on debt	(283,442		)	—			—			(283,442		)
	Intercompany transfers	—			(3,041		)	3,041			—
	Other financing activities	(2,336		)	—			—			(2,336		)
	Change in cash and cash equivalents	240,183			—			—			240,183
	Beginning cash and cash equivalents	54,545			50			—			54,595
	Ending cash and cash equivalents	$	294,728		$	50		$	—		$	294,778
		Nine Months Ended September 30, 2013
		Parent			Guarantor			Intercompany			Consolidated
		Issuer			Subsidiaries			Eliminations
		(in thousands)
	Cash flows from operating activities	$	180,399		$	15,903		$	—		$	196,302
	Cash flows from investing activities:
	Additions to oil and gas properties, including acquisitions	(303,774		)	(31,823		)	—			(335,597		)
	Additions to furniture, fixtures and other	(1,506		)	—			—			(1,506		)
	Proceeds from sale of properties and other investing activities	784			—			—			784
	Cash flows from financing activities:
	Proceeds from debt	390,000			—			—			390,000
	Principal payments on debt	(269,125		)	—			—			(269,125		)
	Intercompany transfers	(15,920		)	15,920			—			—
	Other financing activities	227			—			—			227
	Change in cash and cash equivalents	(18,915		)	—			—			(18,915		)
	Beginning cash and cash equivalents	79,395			50			—			79,445
	Ending cash and cash equivalents	$	60,480		$	50		$	—		$	60,530

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	$26,700	$216,600	$27,800	$216,600
5% Convertible Senior Notes Due 2028	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Debt, stated interest rate	5.00%	'	5.00%	'
Proved Oil And Gas Properties [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	11,493	198,787	12,531	198,787
West Tavaputs [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	'	2,500	1,000	'
Alberta [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	'	15,300	'	'
Unproved Oil And Gas Properties [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	15,250	17,777	15,250	17,777
Proved, Powder River Oil and Paradox [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	'	'	$11,500	'

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Summary of Accounts Receivable (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Allowance for doubtful accounts	($14)	($21)
Accounts receivable	88,554	97,586
Accrued Oil, Gas, and NGL Sales	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Accounts receivable gross	58,175	67,583
Due from Joint Interest Owners	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Accounts receivable gross	25,339	23,507
Other	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Accounts receivable gross	$5,054	$6,517

Summary_of_Significant_Account5

Summary of Significant Accounting Policies - Net Capitalized Costs and Associated Accumulated Depreciation, Depletion & Amortization and Non Cash Impairments (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accounting Policies [Abstract]	'	'
Proved properties	$382,867	$485,427
Wells and related equipment and facilities	1,406,678	2,192,754
Support equipment and facilities	60,588	177,224
Materials and supplies	13,345	8,518
Total proved oil and gas properties	1,863,478	2,863,923
Unproved properties	185,237	239,925
Wells and facilities in progress	97,585	56,674
Total unproved oil and gas properties, excluded from amortization	282,822	296,599
Accumulated depreciation, depletion, amortization and impairment	-443,748	-976,339
Total oil and gas properties, net	$1,702,552	$2,184,183

Summary_of_Significant_Account6

Summary of Significant Accounting Policies - Non-Cash Impairment Charges, Included within Impairment, Dry Hole Costs and Abandonment Expense in Consolidated Statements of Operations (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	$26,700	$216,600	$27,800	$216,600
Dry hole costs	3	-36	96	928
Abandonment expense	2,363	2,835	4,396	10,154
Impairment, dry hole costs and abandonment expense	29,109	219,363	32,613	227,646
Proved Oil And Gas Properties [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	11,493	198,787	12,531	198,787
Unproved Oil And Gas Properties [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of oil and gas properties	15,250	17,777	15,250	17,777
Non Cash Impairment Of Inventory [Member]	'	'	'	'
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'
Non-cash impairment of inventory	$0	$0	$340	$0

Summary_of_Significant_Account7

Summary of Significant Accounting Policies - Accounts Payable and Accrued Liabilities (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accounting Policies [Abstract]	'	'
Accrued drilling, completion and facility costs	$85,517	$54,750
Accrued lease operating, gathering, transportation and processing expenses	13,025	17,317
Accrued general and administrative expenses	7,042	14,605
Trade payables and other	49,336	29,256
Total accounts payable and accrued liabilities	$154,920	$115,928

Summary_of_Significant_Account8

Summary of Significant Accounting Policies - Calculation of Basic and Diluted Earnings (Loss) Per Share (Detail) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Accounting Policies [Abstract]	'	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,336,252	2,450,539	1,199,451	2,731,578	'
Net Loss	($34,649)	($166,656)	($73,984)	($185,534)	($192,733)
Basic weighted-average common shares outstanding in period (in shares)	48,060,086	47,535,124	47,982,992	47,452,865	'
Add dilutive effects of stock options and nonvested equity shares of common stock (in shares)	0	0	0	0	'
Diluted weighted-average common shares outstanding in period (in shares)	48,060,086	47,535,124	47,982,992	47,452,865	'
Net Income (Loss) Per Common Share, Basic (in dollars per share)	($0.72)	($3.51)	($1.54)	($3.91)	'
Net Income (Loss) Per Common Share, Diluted (in dollars per share)	($0.72)	($3.51)	($1.54)	($3.91)	'

Supplemental_Disclosures_of_Ca2

Supplemental Disclosures of Cash Flow Information - Supplemental Cash Flow Information (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Supplemental Cash Flow Information [Abstract]	'	'
Cash paid for interest	$36,267	$61,796
Cash paid for income taxes	1	1,861
Supplemental disclosures of non-cash investing and financing activities:	'	'
Current liabilities	90,381	75,265
Net increase (decrease) in asset retirement obligations	-23,327	2,924
Retirement of treasury stock	-2,462	-1,415
Fair Value of Properties Exchanged in Non-Cash Transactions	77,078	0
Relief of Lease Financing Obligation	$36,106	$45,190

Divestitures_Details

Divestitures (Details) (USD $)	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended	3 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Sep. 30, 2014
						West Tavaputs [Member]	West Tavaputs [Member]	Powder River Oil [Member]	Piceance [Member]
								acre
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'	'	'	'	'	'
Proceeds from sale of businesses	'	'	'	'	'	'	$308,700,000	$27,400,000	$503,600,000
Relief of Asset Retirement Obligation	'	'	'	'	'	'	'	1,300,000	22,448,000
Net Mineral Acres Sold	'	'	'	'	'	'	'	17,497	'
Net Mineral Acres Exchanged Relinquished	'	'	'	'	'	'	'	29,015	'
Net Mineral Acres Exchanged Received	'	'	'	'	'	'	'	7,856	'
Assets, Fair Value Disclosure, Nonrecurring	'	'	'	'	'	'	'	71,000,000	'
Proved Oil and Gas Assets Sold or Exchanged	'	'	'	'	'	'	'	85,700,000	1,320,757,000
Unproved Oil and Gas Assets Sold	'	'	'	'	'	'	'	39,700,000	'
Accumulated Depreciation Depletion Amortization And Impairment Property Plant And Equipment	469,015,000	'	469,015,000	'	999,752,000	'	'	33,100,000	'
Relief of Lease Financing Obligation	-36,106,000	-45,190,000	-36,106,000	-45,190,000	'	'	'	'	36,106,000
Loss on Divestitures	-99,466,000	0	-96,896,000	0	'	'	'	25,700,000	74,800,000
Impairment loss recognized	'	'	'	'	'	$1,000,000	$209,500,000	'	'

Divestitures_Divestitures_Deta

Divestitures Divestitures (Details 2) (USD $)	Sep. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'
Relief of Lease Financing Obligation	($36,106)	($45,190)
Piceance [Member]	'	'
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'
Proved Oil and Gas Assets Sold or Exchanged	1,320,757	'
Furniture, Equipment and Other Sold	4,907	'
Accumulated Depreciation, Depletion, Amortization and Impairment Sold	-688,864	'
Other Assets Sold	173	'
Total Assets Sold	636,973	'
Relief of Asset Retirement Obligation	22,448	'
Relief of Lease Financing Obligation	36,106	'
Total Liabilities Sold	58,554	'
Net Assets Sold	$578,419	'

LongTerm_Debt_Outstanding_Debt

Long-Term Debt - Outstanding Debt (Detail) (USD $)

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Mar. 31, 2012

Sep. 30, 2014

Dec. 31, 2013

Sep. 27, 2011

Sep. 30, 2014

Dec. 31, 2013

Mar. 12, 2012

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Amended Credit Facility

Amended Credit Facility

Convertible Notes

Convertible Notes

Convertible Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

Lease Financing Obligation

Lease Financing Obligation

Long-term Debt

Long-term Debt

Current Portion of Long-Term Debt

Current Portion of Long-Term Debt

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Maturity Date

'

'

31-Oct-16

'

15-Mar-28

'

'

1-Oct-19

'

'

15-Oct-22

'

'

10-Aug-20

'

'

'

'

'

Principal amount of debt instrument

$828,624,000

$979,082,000

$0

$115,000,000

$25,344,000

$25,344,000

$25,300,000

$400,000,000

$400,000,000

$400,000,000

$400,000,000

$400,000,000

$400,000,000

$3,721,000

$43,329,000

$829,065,000

$983,673,000

$441,000

$4,591,000

Discount

0

0

0

0

0

0

'

0

0

'

0

0

'

0

0

0

0

0

0

Carrying Amount

828,624,000

979,082,000

0

115,000,000

25,344,000

25,344,000

'

400,000,000

400,000,000

'

400,000,000

400,000,000

'

3,721,000

43,329,000

829,065,000

983,673,000

441,000

4,591,000

Aggregate fair value of convertible notes

'

'

'

'

25,400,000

25,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt, stated interest rate

'

'

'

'

5.00%

'

'

7.63%

7.63%

'

7.00%

7.00%

'

'

'

'

'

'

'

Debt, fair value

$823,300,000

$847,200,000

$0

$115,000,000

$25,400,000

$25,100,000

'

$407,300,000

$430,200,000

'

$416,000,000

$417,000,000

'

$3,500,000

$41,700,000

'

'

'

'

LongTerm_Debt_LongTerm_Debt_Ad

Long-Term Debt Long-Term Debt - Additional Information (Detail) (USD $)

3 Months Ended

9 Months Ended

9 Months Ended

1 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

9 Months Ended

1 Months Ended

9 Months Ended

9 Months Ended

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Mar. 20, 2012

Sep. 30, 2014

Mar. 12, 2008

Sep. 30, 2014

Dec. 31, 2013

Mar. 31, 2012

Sep. 27, 2011

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Mar. 12, 2012

Jul. 23, 2012

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Amended Credit Facility

Amended Credit Facility

5% Convertible Senior Notes

5% Convertible Senior Notes

5% Convertible Senior Notes

Convertible Notes

Convertible Notes

Convertible Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

9.875% Senior Notes

Minimum

Maximum

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, maturity date

'

'

'

'

'

31-Oct-16

'

'

'

'

15-Mar-28

'

'

'

1-Oct-19

'

15-Oct-22

'

'

'

10-Aug-20

'

'

'

'

Line of credit facility, maximum borrowing capacity

$375,000,000

'

$375,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revolving credit facility, interest rate above London Interbank Offered Rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.50%

2.50%

Revolving credit facility interest rate percent above LIBOR alternate interest rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.50%

1.50%

Commitment fee percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.38%

0.50%

Average annual interest rates incurred on Amended Credit Facility

2.00%

2.10%

1.90%

2.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Letters of credit issued amount

'

'

'

'

'

26,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of credit facility, remaining borrowing capacity

349,000,000

'

349,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Principal amount

828,624,000

'

828,624,000

'

979,082,000

0

115,000,000

'

'

172,500,000

25,344,000

25,344,000

25,300,000

400,000,000

400,000,000

400,000,000

400,000,000

400,000,000

400,000,000

'

3,721,000

43,329,000

'

'

'

Face Amount of Outstanding Convertible Notes Repaid

'

'

'

'

'

'

'

147,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of notes put to company

'

'

'

'

'

'

'

85.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt, stated interest rate

'

'

'

'

'

'

'

'

5.00%

'

5.00%

'

'

'

7.63%

7.63%

7.00%

7.00%

'

'

'

'

9.88%

'

'

Sale and subsequent lease back

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100,800,000

'

'

'

'

'

Par value of senior notes

'

'

'

'

'

'

'

'

'

'

'

'

'

103.81%

'

'

103.50%

'

'

'

'

'

'

'

'

Debt instrument conversion price rate of redemption

'

'

'

'

'

'

'

'

'

'

100.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Minimum days notice to call Convertible Notes

'

'

'

'

'

'

'

'

'

'

'30 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Purchase of equipment

$1,800,000

'

$1,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$36,600,000

'

'

'

'

Weighted average implicit rate based on interest expense

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3.30%

'

'

'

'

Percent Of Financing Obligation Sold

51.00%

'

51.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

LongTerm_Debt_Cash_and_NonCash

Long-Term Debt - Cash and Non-Cash Portion of Interest Expense Related to Long Term Debt (Detail) (USD $)

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Dec. 31, 2013

Mar. 31, 2012

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 27, 2011

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Dec. 31, 2013

Mar. 12, 2012

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Jul. 23, 2012

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

9.875% Senior Notes

9.875% Senior Notes

9.875% Senior Notes

9.875% Senior Notes

9.875% Senior Notes

9.875% Senior Notes

9.875% Senior Notes

9.875% Senior Notes

9.875% Senior Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

Convertible Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.625% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

7.0% Senior Notes

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Lease Financing Obligation

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Non-cash interest [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amended Credit Facility interest

'

'

$1,771,000

$2,296,000

$4,392,000

$4,211,000

$586,000

$585,000

$1,757,000

$1,756,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Senior Notes interest

'

'

'

'

'

'

'

'

'

'

'

0

1,029,000

0

13,373,000

0

0

0

1,361,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,625,000

7,625,000

22,875,000

22,875,000

273,000

272,000

817,000

798,000

'

'

'

7,000,000

7,000,000

21,000,000

21,000,000

204,000

203,000

610,000

592,000

'

'

'

'

'

'

'

'

'

'

'

Convertible Notes interest

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

306,000

310,000

940,000

943,000

1,000

1,000

4,000

4,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Financial Obligation interest

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

248,000

750,000

765,000

2,305,000

3,000

8,000

11,000

24,000

Debt, stated interest rate

'

'

'

'

'

'

'

'

'

'

9.88%

'

'

'

'

'

'

'

'

5.00%

'

'

'

'

'

'

'

'

'

'

7.63%

7.63%

'

'

'

'

'

'

'

'

'

7.00%

7.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Effective interest rate of debt instrument

'

'

'

'

'

'

'

'

'

'

11.20%

'

'

'

'

'

'

'

'

5.00%

'

'

'

'

'

'

'

'

'

'

8.00%

'

'

'

'

'

'

'

'

'

'

7.20%

'

'

'

'

'

'

'

'

'

'

'

3.30%

'

'

'

'

'

'

'

'

'

Principal amount of debt instrument

828,624,000

979,082,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

25,344,000

25,344,000

25,300,000

'

'

'

'

'

'

'

'

400,000,000

400,000,000

400,000,000

'

'

'

'

'

'

'

'

400,000,000

400,000,000

400,000,000

'

'

'

'

'

'

'

'

'

3,721,000

43,329,000

'

'

'

'

'

'

'

'

Percent of Financing Obligation held-for-sale

51.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Sale and subsequent lease back

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$100,800,000

'

'

'

'

'

'

'

'

'

'

Asset_Retirement_Obligations_S

Asset Retirement Obligations - Schedule of Asset Retirement Obligations (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]	'
As of December 31, 2013	$43,005
Liabilities incurred	3,627
Liabilities settled	-4,383
Disposition of properties	-23,722
Accretion expense	2,532
Revisions to estimate	1,151
As of September 30, 2014	22,210
Less: Current asset retirement obligations	2,641
Long-term asset retirement obligations	$19,569

Fair_Value_Measurements_Fair_V

Fair Value Measurements - Fair Value, Balance Sheet Grouping (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets	'	'	'	'
Deferred Compensation Plan	$914	$941	'	'
Cash Equivalents	294,778	54,595	60,530	79,445
Cash Equivalents - Money Market Funds	'	'	'	'
Assets	'	'	'	'
Cash Equivalents	53	53	'	'
Commodity Derivatives	'	'	'	'
Assets	'	'	'	'
Commodity Derivatives	20,530	11,483	'	'
Liabilities	'	'	'	'
Commodity Derivatives	2,757	14,771	'	'
Level 1	'	'	'	'
Assets	'	'	'	'
Deferred Compensation Plan	914	941	'	'
Level 1 | Cash Equivalents - Money Market Funds	'	'	'	'
Assets	'	'	'	'
Cash Equivalents	53	53	'	'
Level 1 | Commodity Derivatives	'	'	'	'
Assets	'	'	'	'
Commodity Derivatives	0	0	'	'
Liabilities	'	'	'	'
Commodity Derivatives	0	0	'	'
Level 2	'	'	'	'
Assets	'	'	'	'
Deferred Compensation Plan	0	0	'	'
Level 2 | Cash Equivalents - Money Market Funds	'	'	'	'
Assets	'	'	'	'
Cash Equivalents	0	0	'	'
Level 2 | Commodity Derivatives	'	'	'	'
Assets	'	'	'	'
Commodity Derivatives	20,530	11,483	'	'
Liabilities	'	'	'	'
Commodity Derivatives	2,757	14,771	'	'
Level 3	'	'	'	'
Assets	'	'	'	'
Deferred Compensation Plan	0	0	'	'
Level 3 | Cash Equivalents - Money Market Funds	'	'	'	'
Assets	'	'	'	'
Cash Equivalents	0	0	'	'
Level 3 | Commodity Derivatives	'	'	'	'
Assets	'	'	'	'
Commodity Derivatives	0	0	'	'
Liabilities	'	'	'	'
Commodity Derivatives	$0	$0	'	'

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Fair Value Measurements [Line Items]	'	'	'	'	'
Debt, fair value	$823,300,000	'	$823,300,000	'	$847,200,000
Impairment of Oil and Gas Properties	26,700,000	216,600,000	27,800,000	216,600,000	'
7.625% Senior Notes	'	'	'	'	'
Fair Value Measurements [Line Items]	'	'	'	'	'
Debt, stated interest rate	7.63%	'	7.63%	'	7.63%
Debt, fair value	407,300,000	'	407,300,000	'	430,200,000
7.0% Senior Notes	'	'	'	'	'
Fair Value Measurements [Line Items]	'	'	'	'	'
Debt, stated interest rate	7.00%	'	7.00%	'	7.00%
Debt, fair value	416,000,000	'	416,000,000	'	417,000,000
Amended Credit Facility	'	'	'	'	'
Fair Value Measurements [Line Items]	'	'	'	'	'
Debt, fair value	0	'	0	'	115,000,000
Convertible Notes	'	'	'	'	'
Fair Value Measurements [Line Items]	'	'	'	'	'
Debt, stated interest rate	5.00%	'	5.00%	'	'
Debt, fair value	25,400,000	'	25,400,000	'	25,100,000
Lease Financing Obligation	'	'	'	'	'
Fair Value Measurements [Line Items]	'	'	'	'	'
Debt, fair value	$3,500,000	'	$3,500,000	'	$41,700,000

Derivative_Instruments_Fair_Va

Derivative Instruments - Fair Value Amounts of Derivative Instruments (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Derivatives, Fair Value [Line Items]	'	'
Gross Amounts of Recognized Derivative Assets	$20,530,000	$11,483,000
Gross Amounts Offset in the Balance Sheet	-2,757,000	-8,771,000
Net Amounts of Derivative Assets Presented in the Balance Sheet	17,773,000	2,712,000
Gross Amounts of Recognized Derivative Liabilities	-2,757,000	-14,771,000
Gross Amounts Offset in the Balance Sheet	2,757,000	8,771,000
Net Amounts of Derivative Liabilities Presented in the Balance Sheet	0	-6,000,000
Balance included in other noncurrent liabilities excluding deferred financing costs and other noncurrent assets	16,400,000	19,200,000
Derivative assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Gross Amounts of Recognized Derivative Assets	13,623,000	8,259,000
Gross Amounts Offset in the Balance Sheet	-2,528,000	-8,086,000
Net Amounts of Derivative Assets Presented in the Balance Sheet	11,095,000	173,000
Deferred financing costs and other noncurrent assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Gross Amounts of Recognized Derivative Assets	6,907,000	3,224,000
Gross Amounts Offset in the Balance Sheet	-229,000	-685,000
Net Amounts of Derivative Assets Presented in the Balance Sheet	6,678,000	2,539,000
Derivative liabilities	'	'
Derivatives, Fair Value [Line Items]	'	'
Gross Amounts of Recognized Derivative Liabilities	-2,528,000	-14,074,000
Gross Amounts Offset in the Balance Sheet	2,528,000	8,086,000
Net Amounts of Derivative Liabilities Presented in the Balance Sheet	0	-5,988,000
Derivative Financial Instruments, Liabilities	'	'
Derivatives, Fair Value [Line Items]	'	'
Balance included in other noncurrent liabilities excluding hedge instruments	3,000,000	3,500,000
Derivatives and other noncurrent liabilities	'	'
Derivatives, Fair Value [Line Items]	'	'
Gross Amounts of Recognized Derivative Liabilities	-229,000	-697,000
Gross Amounts Offset in the Balance Sheet	229,000	685,000
Net Amounts of Derivative Liabilities Presented in the Balance Sheet	$0	($12,000)

Derivative_Instruments_Cash_Fl

Derivative Instruments - Cash Flow Hedge Gain and Losses (Detail) (USD $)	9 Months Ended	12 Months Ended	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
			Commodity Derivatives	Commodity Derivatives	Commodity Derivatives	Commodity Derivatives
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'	'	'
Derivatives Qualifying as Cash Flow Hedges	'	'	'	'	'CommodityB Hedges	'
Amount of Gain (Loss) Reclassified from AOCI into Income (net of tax)	'	'	$219	$1,186	$555	$3,688
Effect of derivative financial instruments, taxes	$334	$2,802	$100	$700	$300	$2,200

Derivative_Instruments_Financi

Derivative Instruments - Financial Instruments for Hedging Volume (Detail)	Sep. 30, 2014
	MMBTU
	bbl
October b December 2014	'
Derivative Instruments, Gain (Loss) [Line Items]	'
Oil (Bbls)	975,200
Natural gas (MMbtu)	1,762,500
Natural gas liquids (Bbls)	0
For the year 2015	'
Derivative Instruments, Gain (Loss) [Line Items]	'
Oil (Bbls)	4,077,500
Natural gas (MMbtu)	7,300,000
Natural gas liquids (Bbls)	0
For the year 2016	'
Derivative Instruments, Gain (Loss) [Line Items]	'
Oil (Bbls)	1,554,000
Natural gas (MMbtu)	1,830,000
Natural gas liquids (Bbls)	0
For the year 2017	'
Derivative Instruments, Gain (Loss) [Line Items]	'
Oil (Bbls)	182,500
Natural gas (MMbtu)	0
Natural gas liquids (Bbls)	0

Derivative_Instruments_Realize

Derivative Instruments - Realized and Unrealized Gains and Losses on Commodity Derivative Instruments (Detail) (Oil and Natural Gas Derivative Instruments, USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Oil and Natural Gas Derivative Instruments	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Commodity Derivative Settlements On Derivatives Designated As Cash Flow Hedges	$351	$1,899	$889	$5,902
Total commodity derivative gain (loss)	$72,299	($25,595)	$369	($18,607)

Derivative_Instruments_Additio

Derivative Instruments - Additional Information (Detail)	3 Months Ended
	Sep. 30, 2014
	Counterparty
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Number of counterparties for hedges at period end	8

Equity_Incentive_Compensation_2

Equity Incentive Compensation Plans and Other Employee Benefits - Non-Cash Stock-Based Compensation Cost Related to Equity Awards (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Stock Based Compensation [Line Items]	'	'	'	'
Non-cash stock-based compensation equity awards	$3,471	$3,232	$9,289	$11,847
Common Stock Options	'	'	'	'
Stock Based Compensation [Line Items]	'	'	'	'
Non-cash stock-based compensation equity awards	482	681	1,608	3,898
Nonvested Equity Common Stock	'	'	'	'
Stock Based Compensation [Line Items]	'	'	'	'
Non-cash stock-based compensation equity awards	1,760	1,562	4,979	5,550
Nonvested Equity Common Stock Units	'	'	'	'
Stock Based Compensation [Line Items]	'	'	'	'
Non-cash stock-based compensation equity awards	274	277	783	989
Nonvested Performance-Based Equity	'	'	'	'
Stock Based Compensation [Line Items]	'	'	'	'
Non-cash stock-based compensation equity awards	$955	$712	$1,919	$1,410

Equity_Incentive_Compensation_3

Equity Incentive Compensation Plans and Other Employee Benefits - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended		1 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Feb. 28, 2014	Feb. 28, 2014	Mar. 31, 2012
					2014 Performance Program	2014 Performance Program	2014 Performance Program
						Maximum	Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'	'	'
Unrecognized compensation cost	$21,600,000	'	$21,600,000	'	'	'	'
Weighted-average period (years)	'	'	'2 years 6 months	'	'	'	'
Weighted Percentage Of Stockholders Return Related To Performance Goals	'	'	'	'	60.00%	'	'
Performance Goals Percentage for Change In Discretionary Cash Flow Per Debt Adjusted Share Relative To Defined Peer Groups Percentage	'	'	'	'	40.00%	'	'
Percentage Of Grant That Will Vest For Performance Met At Threshold Level	'	'	'	'	'	25.00%	'
Percentage of total grant that will vest for metrics met at target level	'	'	'	'	'	100.00%	'
Percentage of total grant that will vest for metrics met at stretch level	'	'	'	'	'	200.00%	200.00%
Non-cash stock based compensation	$3,471,000	$3,232,000	$9,289,000	$11,847,000	'	'	'

Equity_Incentive_Compensation_4

Equity Incentive Compensation Plans and Other Employee Benefits - Stock Options and Nonvested Equity Shares, Equity Awards Granted (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'	'	'	'
Nonvested equity shares, Number of Shares	26,828	57,792	516,768	615,052
Nonvested equity common stock units, Number of Shares	850	2,210	44,282	54,429
Nonvested performance-based equity shares, Number of Shares	10,073	154,314	303,188	442,300
Total shares granted	37,751	214,316	864,238	1,111,781
Nonvested equity shares, Weighted Average Grant Date Fair Value	$21.53	$22.36	$22.49	$17.80
Nonvested equity common stock units, Weighted Average Grant Date Fair Value	$22.04	$25.11	$24.98	$22.17
Nonvested performance-based equity shares, Weighted Average Grant Date Fair Value	$18.52	$20.86	$19.77	$18.08

Commitments_and_Contingencies_1

Commitments and Contingencies - Schedule of Aggregate Undiscounted Minimum Future Lease Payments (Detail) (Lease Financing Obligation, USD $)	Sep. 30, 2014
In Thousands, unless otherwise specified
Lease Financing Obligation	'
Future Minimum Lease Payments Under Capital Leases And Operating Leases For Continuing Operations [Line Items]	'
2014	$134
2015	537
2016	537
2017	537
2018	537
Thereafter	1,826
Total	$4,108

Commitments_and_Contingencies_2

Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Dec. 01, 2014	Sep. 30, 2014	Sep. 30, 2014
	MMcf	Agreement	Maximum	Scenario, Forecast [Member]	Commitment Ending November 30, 2014 [Member]	Commitment Ending November 30, 2015 [Member]
		MMcf			MMcf	MMcf
Contingencies And Commitments [Line Items]	'	'	'	'	'	'
Contract term, years	'	'	'7 years	'	'	'
Number of take-or-pay purchase agreements for supply of carbon dioxide	'	1	'	'	'	'
Total financial commitment on take-or-pay purchase agreements for supply of carbon dioxide	$1.70	'	'	'	'	'
Minimum Volume Commitment	'	'	'	'	380	450
Deficiency payment for not meeting delivery commitments	0.6	0.6	'	'	'	'
Minimum Volume Commitment Deficiency Payment	0.8	0.8	'	'	'	'
Minimum Volume Commitment, Volumes Satisfied	172	172	'	'	'	'
Minimum Volume Commitment, Estimated Deficiency Payment	'	'	'	$0.30	'	'

Commitments_and_Contingencies_3

Commitments and Contingencies - Gross Future Minimum Transportation Demand and Firm Processing Charges (Detail) (USD $)	Sep. 30, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'
2014	$4,577
2015	18,692
2016	18,692
2017	18,692
2018	18,692
Thereafter	48,287
Total	$127,632

Commitments_and_Contingencies_4

Commitments and Contingencies - Future Minimum Annual Payments under Drilling, Lease and Other Agreements (Detail) (Office & Equipment Leases, USD $)	Sep. 30, 2014
In Thousands, unless otherwise specified
Office & Equipment Leases	'
Operating Leased Assets [Line Items]	'
2014	$1,322
2015	3,968
2016	2,817
2017	2,612
2018	2,528
Thereafter	633
Total	$13,880

Guarantor_Subsidiaries_Additio

Guarantor Subsidiaries - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Dec. 31, 2013
		9.875% Senior Notes	7.625% Senior Notes	7.625% Senior Notes	7.0% Senior Notes	7.0% Senior Notes
Guarantor Subsidiaries [Line Items]	'	'	'	'	'	'
Debt, stated interest rate	'	9.88%	7.63%	7.63%	7.00%	7.00%
Percentage of Guarantor Subsidiaries	100.00%	'	'	'	'	'

Guarantor_Subsidiaries_Schedul

Guarantor Subsidiaries - Schedule of Condensed Consolidating Balance Sheets (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets:	'	'	'
Current assets	$397,942	$157,247	'
Property and equipment, net	1,716,253	2,202,496	'
Intercompany receivable (payable)	0	0	'
Investment in subsidiaries	0	0	'
Noncurrent assets	23,089	21,770	'
Total	2,137,284	2,381,513	'
Liabilities and Stockholders' Equity:	'	'	'
Current liabilities	233,626	192,719	'
Long-term debt	828,624	979,082	'
Deferred income taxes	113,524	161,326	'
Other noncurrent liabilities	22,566	42,668	'
Stockholders' equity	938,944	1,005,718	1,182,775
Total liabilities and stockholders' equity	2,137,284	2,381,513	'
Parent Issuer	'	'	'
Assets:	'	'	'
Current assets	397,890	154,986	'
Property and equipment, net	1,636,831	2,127,624	'
Intercompany receivable (payable)	55,634	59,076	'
Investment in subsidiaries	18,179	12,063	'
Noncurrent assets	23,089	21,770	'
Total	2,131,623	2,375,519	'
Liabilities and Stockholders' Equity:	'	'	'
Current liabilities	232,748	192,106	'
Long-term debt	828,624	979,082	'
Deferred income taxes	110,269	158,071	'
Other noncurrent liabilities	21,038	40,542	'
Stockholders' equity	938,944	1,005,718	'
Total liabilities and stockholders' equity	2,131,623	2,375,519	'
Guarantor Subsidiaries	'	'	'
Assets:	'	'	'
Current assets	52	2,261	'
Property and equipment, net	79,422	74,872	'
Intercompany receivable (payable)	-55,634	-59,076	'
Investment in subsidiaries	0	0	'
Noncurrent assets	0	0	'
Total	23,840	18,057	'
Liabilities and Stockholders' Equity:	'	'	'
Current liabilities	878	613	'
Long-term debt	0	0	'
Deferred income taxes	3,255	3,255	'
Other noncurrent liabilities	1,528	2,126	'
Stockholders' equity	18,179	12,063	'
Total liabilities and stockholders' equity	23,840	18,057	'
Intercompany Eliminations	'	'	'
Assets:	'	'	'
Current assets	0	0	'
Property and equipment, net	0	0	'
Intercompany receivable (payable)	0	0	'
Investment in subsidiaries	-18,179	-12,063	'
Noncurrent assets	0	0	'
Total	-18,179	-12,063	'
Liabilities and Stockholders' Equity:	'	'	'
Current liabilities	0	0	'
Long-term debt	0	0	'
Deferred income taxes	0	0	'
Other noncurrent liabilities	0	0	'
Stockholders' equity	-18,179	-12,063	'
Total liabilities and stockholders' equity	($18,179)	($12,063)	'

Guarantor_Subsidiaries_Schedul1

Guarantor Subsidiaries - Schedule of Condensed Consolidating Statements of Operations (Detail) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Operating and other revenues	$135,263	$148,555	$405,389	$429,131	'
Operating expenses	-235,185	-334,223	-429,752	-568,437	'
General and administrative	-11,111	-14,402	-41,039	-48,257	'
Interest and other income (expense)	54,530	-67,081	-51,925	-109,290	'
Income (loss) before income taxes and equity in earnings (loss) of subsidiaries	-56,503	-267,151	-117,327	-296,853	'
(Provision for) Benefit from Income Taxes	21,854	100,495	43,343	111,319	'
Equity in earnings (loss) of subsidiaries	0	0	0	0	'
Net Loss	-34,649	-166,656	-73,984	-185,534	-192,733
Parent Issuer	'	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Operating and other revenues	128,235	139,689	385,703	407,048	'
Operating expenses	-230,021	-329,949	-416,147	-556,811	'
General and administrative	-11,111	-14,402	-41,039	-48,257	'
Interest and other income (expense)	54,530	-67,081	-51,960	-109,290	'
Income (loss) before income taxes and equity in earnings (loss) of subsidiaries	-58,367	-271,743	-123,443	-307,310	'
(Provision for) Benefit from Income Taxes	21,854	100,495	43,343	111,319	'
Equity in earnings (loss) of subsidiaries	1,864	4,592	6,116	10,457	'
Net Loss	-34,649	-166,656	-73,984	-185,534	'
Guarantor Subsidiaries	'	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Operating and other revenues	7,028	8,866	19,686	22,083	'
Operating expenses	-5,164	-4,274	-13,605	-11,626	'
General and administrative	0	0	0	0	'
Interest and other income (expense)	0	0	35	0	'
Income (loss) before income taxes and equity in earnings (loss) of subsidiaries	1,864	4,592	6,116	10,457	'
(Provision for) Benefit from Income Taxes	0	0	0	0	'
Equity in earnings (loss) of subsidiaries	0	0	0	0	'
Net Loss	1,864	4,592	6,116	10,457	'
Intercompany Eliminations	'	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Operating and other revenues	0	0	0	0	'
Operating expenses	0	0	0	0	'
General and administrative	0	0	0	0	'
Interest and other income (expense)	0	0	0	0	'
Income (loss) before income taxes and equity in earnings (loss) of subsidiaries	0	0	0	0	'
(Provision for) Benefit from Income Taxes	0	0	0	0	'
Equity in earnings (loss) of subsidiaries	-1,864	-4,592	-6,116	-10,457	'
Net Loss	($1,864)	($4,592)	($6,116)	($10,457)	'

Guarantor_Subsidiaries_Schedul2

Guarantor Subsidiaries - Schedule of Condensed Consolidating Statements of Comprehensive Income (Loss) (Detail) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Net income (loss)	($34,649)	($166,656)	($73,984)	($185,534)	($192,733)
Effect of derivative financial instruments	-219	-1,186	-555	-3,688	-4,663
Other comprehensive income (loss)	-219	-1,186	-555	-3,688	'
Comprehensive Loss	-34,868	-167,842	-74,539	-189,222	'
Parent Issuer	'	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Net income (loss)	-34,649	-166,656	-73,984	-185,534	'
Effect of derivative financial instruments	-219	-1,186	-555	-3,688	'
Other comprehensive income (loss)	-219	-1,186	-555	-3,688	'
Comprehensive Loss	-34,868	-167,842	-74,539	-189,222	'
Guarantor Subsidiaries	'	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Net income (loss)	1,864	4,592	6,116	10,457	'
Effect of derivative financial instruments	0	0	0	0	'
Other comprehensive income (loss)	0	0	0	0	'
Comprehensive Loss	1,864	4,592	6,116	10,457	'
Intercompany Eliminations	'	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'
Net income (loss)	-1,864	-4,592	-6,116	-10,457	'
Effect of derivative financial instruments	0	0	0	0	'
Other comprehensive income (loss)	0	0	0	0	'
Comprehensive Loss	($1,864)	($4,592)	($6,116)	($10,457)	'

Guarantor_Subsidiaries_Schedul3

Guarantor Subsidiaries - Schedule of Condensed Consolidating Statements of Cash Flows (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Condensed Financial Statements, Captions [Line Items]	'	'
Cash flows from operating activities	$231,302	$196,302
Cash flows from investing activities:	'	'
Additions to oil and gas properties, including acquisitions	-425,978	-335,597
Additions to furniture, fixtures and other	-2,110	-1,506
Proceeds from sale of properties and other investing activities	557,747	784
Intercompany Transfers Investing Activities	0	'
Cash flows from financing activities:	'	'
Proceeds from debt	165,000	390,000
Principal payments on debt	-283,442	-269,125
Intercompany Transfer Financing Activities	0	0
Other financing activities	-2,336	227
Increase (Decrease) in Cash and Cash Equivalents	240,183	-18,915
Beginning Cash and Cash Equivalents	54,595	79,445
Ending Cash and Cash Equivalents	294,778	60,530
Parent Issuer	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Cash flows from operating activities	214,521	180,399
Cash flows from investing activities:	'	'
Additions to oil and gas properties, including acquisitions	-410,417	-303,774
Additions to furniture, fixtures and other	-2,110	-1,506
Proceeds from sale of properties and other investing activities	555,926	784
Intercompany Transfers Investing Activities	3,041	'
Cash flows from financing activities:	'	'
Proceeds from debt	165,000	390,000
Principal payments on debt	-283,442	-269,125
Intercompany Transfer Financing Activities	0	-15,920
Other financing activities	-2,336	227
Increase (Decrease) in Cash and Cash Equivalents	240,183	-18,915
Beginning Cash and Cash Equivalents	54,545	79,395
Ending Cash and Cash Equivalents	294,728	'
Guarantor Subsidiaries	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Cash flows from operating activities	16,781	15,903
Cash flows from investing activities:	'	'
Additions to oil and gas properties, including acquisitions	-15,561	-31,823
Additions to furniture, fixtures and other	0	0
Proceeds from sale of properties and other investing activities	1,821	0
Intercompany Transfers Investing Activities	0	'
Cash flows from financing activities:	'	'
Proceeds from debt	0	0
Principal payments on debt	0	0
Intercompany Transfer Financing Activities	-3,041	15,920
Other financing activities	0	0
Increase (Decrease) in Cash and Cash Equivalents	0	0
Beginning Cash and Cash Equivalents	50	50
Ending Cash and Cash Equivalents	50	'
Intercompany Eliminations	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Cash flows from operating activities	0	0
Cash flows from investing activities:	'	'
Additions to oil and gas properties, including acquisitions	0	0
Additions to furniture, fixtures and other	0	0
Proceeds from sale of properties and other investing activities	0	0
Intercompany Transfers Investing Activities	-3,041	'
Cash flows from financing activities:	'	'
Proceeds from debt	0	0
Principal payments on debt	0	0
Intercompany Transfer Financing Activities	3,041	0
Other financing activities	0	0
Increase (Decrease) in Cash and Cash Equivalents	0	0
Beginning Cash and Cash Equivalents	0	0
Ending Cash and Cash Equivalents	$0	'