Gastar Exploration (GST) 10-Q5 Nov 132013 Q3 Quarterly reportFinancial data

Company Profile

Document_And_Entity_Informatio

Document And Entity Information	9 Months Ended
Document And Entity Information	Sep. 30, 2013	Nov. 01, 2013
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Entity Registrant Name	'GASTAR EXPLORATION LTD	'
Entity Central Index Key	'0001170154	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	61,134,950
Gastar Exploration USA Inc.	'	'
Entity Registrant Name	'GASTAR EXPLORATION USA, INC.	'
Entity Central Index Key	'0001431372	'
Entity Filer Category	'Non-accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	750

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
CURRENT ASSETS:	'	'
Cash and cash equivalents	$21,375	$8,901
Accounts receivable, net of allowance for doubtful accounts of $514 and $546, respectively	10,697	9,540
Commodity derivative contracts	2,259	7,799
Prepaid expenses	616	1,097
Total current assets	34,947	27,337
Natural gas and oil properties, full cost method of accounting:	'	'
Unproved properties, excluded from amortization	102,338	67,892
Proved properties	769,054	671,193
Total natural gas and oil properties	871,392	739,085
Furniture and equipment	2,409	1,925
Total property, plant and equipment	873,801	741,010
Accumulated depreciation, depletion and amortization	-506,187	-484,759
Total property, plant and equipment, net	367,614	256,251
OTHER ASSETS:	'	'
Commodity derivative contracts	7,399	1,369
Deferred charges, net	2,133	836
Advances to operators and other assets	12,311	4,275
Total other assets	21,843	6,480
TOTAL ASSETS	424,404	290,068
CURRENT LIABILITIES:	'	'
Accounts payable	5,611	23,863
Revenue payable	12,063	8,801
Accrued interest	6,469	151
Accrued drilling and operating costs	2,727	3,907
Advances from non-operators	12,951	17,540
Commodity derivative contracts	794	1,399
Current commodity derivative premium put payable	1,819	0
Asset retirement obligation	750	358
Other accrued liabilities	8,319	1,493
Total current liabilities	51,503	57,512
LONG-TERM LIABILITIES:	'	'
Long-term debt	194,830	98,000
Commodity derivative contracts	0	1,304
Commodity derivative premium payable	7,651	0
Asset retirement obligation	8,006	6,605
Other long-term liabilities	0	111
Total long-term liabilities	210,487	106,020
Commitments and contingencies (Note 13)	'	'
SHAREHOLDERS' EQUITY:	'	'
Common stock	306,593	316,346
Additional paid-in capital	30,526	28,336
Accumulated deficit	-251,479	-294,787
Total shareholders' equity	85,640	49,895
Non-controlling interest:	'	'
Preferred stock of subsidiary, aggregate liquidation preference $98,954 and $98,781 at September 30, 2013 and December 31, 2012, respectively	76,774	76,641
Total equity	162,414	126,536
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	424,404	290,068
Gastar Exploration USA Inc.	'	'
CURRENT ASSETS:	'	'
Cash and cash equivalents	21,362	8,892
Accounts receivable, net of allowance for doubtful accounts of $514 and $546, respectively	10,696	9,539
Commodity derivative contracts	2,259	7,799
Prepaid expenses	587	919
Total current assets	34,904	27,149
Natural gas and oil properties, full cost method of accounting:	'	'
Unproved properties, excluded from amortization	102,338	67,892
Proved properties	769,046	671,185
Total natural gas and oil properties	871,384	739,077
Furniture and equipment	2,409	1,925
Total property, plant and equipment	873,793	741,002
Accumulated depreciation, depletion and amortization	-506,180	-484,752
Total property, plant and equipment, net	367,613	256,250
OTHER ASSETS:	'	'
Commodity derivative contracts	7,399	1,369
Deferred charges, net	2,133	836
Advances to operators and other assets	12,311	4,275
Total other assets	21,843	6,480
TOTAL ASSETS	424,360	289,879
CURRENT LIABILITIES:	'	'
Accounts payable	5,611	23,863
Revenue payable	12,063	8,801
Accrued interest	6,469	151
Accrued drilling and operating costs	2,727	3,907
Advances from non-operators	12,951	17,540
Commodity derivative contracts	794	1,399
Current commodity derivative premium put payable	1,819	0
Asset retirement obligation	750	358
Other accrued liabilities	7,974	1,480
Total current liabilities	51,158	57,499
LONG-TERM LIABILITIES:	'	'
Long-term debt	194,830	98,000
Commodity derivative contracts	0	1,304
Commodity derivative premium payable	7,651	0
Asset retirement obligation	7,999	6,598
Other long-term liabilities	0	111
Due to parent	34,805	30,903
Total long-term liabilities	245,285	136,916
Commitments and contingencies (Note 13)	'	'
SHAREHOLDERS' EQUITY:	'	'
Preferred stock	40	40
Common stock	225,431	237,431
Additional paid-in capital	76,734	76,601
Accumulated deficit	-174,288	-218,608
Total shareholders' equity	127,917	95,464
Non-controlling interest:	'	'
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$424,360	$289,879

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	9 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Accounts receivable, net of allowance for doubtful accounts	$514	$546
Common stock, par value	$0	$0
Common stock, shares authorized	'unlimited	'unlimited
Common stock, shares issued	61,134,950	66,432,609
Common stock, shares outstanding	61,134,950	66,432,609
Preferred stock of subsidiary, aggregate liquidation preference	98,954	98,781
Gastar Exploration USA Inc.	'	'
Accounts receivable, net of allowance for doubtful accounts	$514	$546
Common stock, shares issued	750	750
Common stock, shares outstanding	750	750
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	3,958,160	3,951,254
Preferred stock, shares outstanding	3,958,160	3,951,254
Liquidation Preference	$25	$25
Common stock, shares authorized	1,000	1,000

Consolidated_Statements_Of_Ope

Consolidated Statements Of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
REVENUES:	'	'	'	'
Natural gas	$11,396	$8,906	$34,673	$22,499
Condensate and oil	8,680	3,457	22,823	7,748
NGLs	3,768	2,483	10,690	6,394
Total natural gas, condensate, oil and NGLs revenues	23,844	14,846	68,186	36,641
Unrealized hedge loss	-5,004	-5,403	-7,156	-4,123
Total revenues	18,840	9,443	61,030	32,518
EXPENSES:	'	'	'	'
Production taxes	1,319	560	3,112	1,494
Lease operating expenses	2,190	780	6,196	4,754
Transportation, treating and gathering	1,098	1,305	3,386	3,715
Depreciation, depletion and amortization	8,467	7,135	21,428	19,744
Impairment recorded (pre-tax) (in thousands)	0	78,054	0	150,787
Accretion of asset retirement obligation	142	101	358	284
General and administrative expense	3,998	2,951	11,964	9,263
Litigation settlement expense	0	0	1,000	1,250
Total expenses	17,214	90,886	47,444	191,291
INCOME (LOSS) FROM OPERATIONS	1,626	-81,443	13,586	-158,773
OTHER INCOME (EXPENSE):	'	'	'	'
Gain on acquisition of assets at fair value	0	0	43,712	0
Interest expense	-3,439	-30	-7,593	-86
Investment income and other	8	2	16	6
Foreign transaction loss	-3	-2	-15	-2
INCOME (LOSS) BEFORE PROVISION FOR INCOME TAXES	-1,808	-81,473	49,706	-158,855
Provision for income taxes	0	0	0	0
NET INCOME (LOSS)	-1,808	-81,473	49,706	-158,855
Dividend on preferred stock attributable to non-controlling interest	-2,134	-1,984	-6,398	-4,947
NET INCOME (LOSS) ATTRIBUTABLE TO GASTAR EXPLORATION LTD.	-3,942	-83,457	43,308	-163,802
NET INCOME (LOSS) PER COMMON SHARE ATTRIBUTABLE TO GASTAR EXPLORATION LTD. COMMON SHAREHOLDERS:	'	'	'	'
Basic (in dollars per share)	($0.07)	($1.31)	$0.71	($2.58)
Diluted (in dollars per share)	($0.07)	($1.31)	$0.68	($2.58)
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING:	'	'	'	'
Basic (shares)	57,359,357	63,601,645	61,159,117	63,494,224
Diluted (shares)	57,359,357	63,601,645	63,971,038	63,494,224
Gastar Exploration USA Inc.	'	'	'	'
REVENUES:	'	'	'	'
Natural gas	11,396	8,906	34,673	22,499
Condensate and oil	8,680	3,457	22,823	7,748
NGLs	3,768	2,483	10,690	6,394
Total natural gas, condensate, oil and NGLs revenues	23,844	14,846	68,186	36,641
Unrealized hedge loss	-5,004	-5,403	-7,156	-4,123
Total revenues	18,840	9,443	61,030	32,518
EXPENSES:	'	'	'	'
Production taxes	1,319	560	3,112	1,494
Lease operating expenses	2,190	780	6,196	4,754
Transportation, treating and gathering	1,098	1,305	3,386	3,715
Depreciation, depletion and amortization	8,467	7,135	21,428	19,744
Impairment recorded (pre-tax) (in thousands)	0	78,054	0	150,787
Accretion of asset retirement obligation	142	101	358	284
General and administrative expense	3,538	2,481	10,935	8,105
Litigation settlement expense	0	0	1,000	1,250
Total expenses	16,754	90,416	46,415	190,133
INCOME (LOSS) FROM OPERATIONS	2,086	-80,973	14,615	-157,615
OTHER INCOME (EXPENSE):	'	'	'	'
Gain on acquisition of assets at fair value	0	0	43,712	0
Interest expense	-3,439	-30	-7,593	-87
Investment income and other	-7	-5	-5	-4
Foreign transaction loss	-3	1	-11	2
INCOME (LOSS) BEFORE PROVISION FOR INCOME TAXES	-1,363	-81,007	50,718	-157,704
Provision for income taxes	0	0	0	0
NET INCOME (LOSS)	-1,363	-81,007	50,718	-157,704
Dividend on preferred stock	-2,134	-1,984	-6,398	-4,947
NET INCOME (LOSS) ATTRIBUTABLE TO GASTAR EXPLORATION LTD.	($3,497)	($82,991)	$44,320	($162,651)

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012
CASH FLOWS FROM OPERATING ACTIVITIES:	'		'
Net income (loss)	$49,706		($158,855)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:	'		'
Depreciation, depletion and amortization	21,428		19,744
Impairment of natural gas and oil properties	0		150,787
Stock-based compensation	2,540		2,575
Unrealized hedge loss	7,156		4,123
Realized loss (gain) on derivative contracts	18		-662
Amortization of deferred financing costs	1,790	[1],[2]	157	[1],[2]
Accretion of asset retirement obligation	-358		-284
Gain on acquisition of assets at fair value	-43,712		0
Changes in operating assets and liabilities:	'		'
Accounts receivable	-1,259		2,429
Prepaid expenses	481		345
Accounts payable and accrued liabilities	733		129
Net cash provided by operating activities	39,239		21,056
CASH FLOWS FROM INVESTING ACTIVITIES:	'		'
Development and purchase of natural gas and oil properties	-77,813		-100,606
Acquisition of natural gas and oil properties	-78,809		0
Proceeds from sale of natural gas and oil properties	70,708		0
Advances to operators	-13,104		-4,282
Use of advances from non-operators	-4,589		-1,085
Purchase of furniture and equipment	-484		-235
Net cash used in investing activities	-104,091		-106,208
CASH FLOWS FROM FINANCING ACTIVITIES:	'		'
Proceeds from revolving credit facility	19,000		70,000
Repayment of revolving credit facility	-117,000		-30,000
Proceeds from issuance of senior secured notes, net of discount	194,500		0
Repurchase of outstanding common shares	-9,753		0
Proceeds from issuance of preferred stock, net of issuance costs	133		49,169
Dividend on preferred stock attributable to non-controlling interest	-6,398		-4,947
Deferred financing charges	-2,807		-332
Other	-349		-282
Net cash provided by financing activities	77,326		83,608
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	12,474		-1,544
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	8,901		10,647
CASH AND CASH EQUIVALENTS, END OF PERIOD	21,375		9,103
Gastar Exploration USA Inc.	'		'
CASH FLOWS FROM OPERATING ACTIVITIES:	'		'
Net income (loss)	50,718		-157,704
Adjustments to reconcile net income (loss) to net cash provided by operating activities:	'		'
Depreciation, depletion and amortization	21,428		19,744
Impairment of natural gas and oil properties	0		150,787
Stock-based compensation	2,540		2,575
Unrealized hedge loss	7,156		4,123
Realized loss (gain) on derivative contracts	18		-662
Amortization of deferred financing costs	1,790		157
Accretion of asset retirement obligation	-358		-284
Gain on acquisition of assets at fair value	-43,712		0
Changes in operating assets and liabilities:	'		'
Accounts receivable	-1,259		2,427
Prepaid expenses	332		215
Accounts payable and accrued liabilities	421		-43
Net cash provided by operating activities	39,790		21,903
CASH FLOWS FROM INVESTING ACTIVITIES:	'		'
Development and purchase of natural gas and oil properties	-77,813		-100,606
Acquisition of natural gas and oil properties	-78,809		0
Proceeds from sale of natural gas and oil properties	70,708		0
Advances to operators	-13,104		-4,282
Use of advances from non-operators	-4,589		-1,085
Purchase of furniture and equipment	-484		-235
Net cash used in investing activities	-104,091		-106,208
CASH FLOWS FROM FINANCING ACTIVITIES:	'		'
Proceeds from revolving credit facility	19,000		70,000
Repayment of revolving credit facility	-117,000		-30,000
Proceeds from issuance of senior secured notes, net of discount	194,500		0
Proceeds from issuance of preferred stock, net of issuance costs	133		49,169
Dividend on preferred stock attributable to non-controlling interest	-6,398		-4,947
Deferred financing charges	-2,807		-332
Distribution to Parent, net	-10,657		-1,196
Other	0		25
Net cash provided by financing activities	76,771		82,719
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	12,470		-1,586
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	8,892		10,595
CASH AND CASH EQUIVALENTS, END OF PERIOD	$21,362		$9,009

[1]	The nine months ended SeptemberB 30, 2013 includes $1.2 million of deferred financing costs written off as a result of the new Revolving Credit Facility. See Note 4, bLong-Term Debt - Second Amended and Restated Revolving Credit Facility.b
[2]	The three and nine months ended SeptemberB 30, 2013 includes $221,000 and $330,000, respectively, of debt discount accretion related to the Notes.

Description_Of_Business

Description Of Business	9 Months Ended
Description Of Business	Sep. 30, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Description of business	'
	Description of Business
	Gastar Exploration Ltd. is an independent energy company engaged in the exploration, development and production of natural gas, condensate, oil and NGLs in the United States (“U.S.”). Gastar Exploration Ltd.’s principal business activities include the identification, acquisition, and subsequent exploration and development of natural gas and oil properties with an emphasis on unconventional reserves, such as shale resource plays. Gastar Exploration Ltd. is currently pursuing the development of liquids-rich natural gas in the Marcellus Shale in West Virginia and is in the early stages of exploring and developing the Hunton Limestone horizontal oil play in Oklahoma. Gastar Exploration Ltd. also holds prospective Marcellus Shale acreage in Pennsylvania. The Company sold substantially all of its East Texas assets on October 2, 2013.
	On August 1, 2013, the shareholders of Gastar Exploration Ltd. voted to approve a special resolution approving a plan of arrangement (as amended, the “Arrangement”) pursuant to which Gastar Exploration Ltd. would be continued as if it had been incorporated under the laws of the State of Delaware (the “Delaware Migration”). On August 2, 2013, Gastar Exploration Ltd. obtained a Final Order from the Court of the Queen's Bench of Alberta, as amended on September 17, 2013 and October 28, 2013, approving the Arrangement. Gastar Exploration Ltd. expects to complete the Delaware Migration in the fourth quarter of 2013.
	Gastar Exploration Ltd. is a holding company and substantially all of its operations are conducted through, and substantially all of its assets are held by, its primary operating subsidiary, Gastar Exploration USA, Inc. and its wholly-owned subsidiaries. Unless otherwise stated or the context requires otherwise, all references in these notes to “Gastar USA” refer collectively to Gastar Exploration USA, Inc. and its wholly-owned subsidiaries, all references to “Parent” refer solely to Gastar Exploration Ltd., and all references to “Gastar,” the “Company” and similar terms refer collectively to Gastar Exploration Ltd. and its subsidiaries, including Gastar Exploration USA, Inc.

Summary_Of_Significant_Account

Summary Of Significant Accounting Policies	9 Months Ended
Summary Of Significant Accounting Policies	Sep. 30, 2013
Accounting Policies [Abstract]	'
Summary Of Significant Accounting Policies	'
	Summary of Significant Accounting Policies
	The accounting policies followed by the Company are set forth in the notes to the Company’s audited consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2012 (as amended, the “2012 Form 10-K”) filed with the SEC. Please refer to the notes to the financial statements included in the 2012 Form 10-K for additional details of the Company’s financial condition, results of operations and cash flows. No material item included in those notes has changed except as a result of normal transactions in the interim or as disclosed within this report.
	These financial statements are a combined presentation of the condensed consolidated financial statements of the Company and Gastar USA. Separate information is provided for the Company and Gastar USA as required. Except as otherwise noted, there are no material differences between the unaudited condensed consolidated information for the Company presented herein and the unaudited condensed consolidated information of Gastar USA.
	The unaudited interim condensed consolidated financial statements of the Company and Gastar USA included herein are stated in U.S. dollars and were prepared from the records of the Company and Gastar USA by management in accordance with U.S. GAAP applicable to interim financial statements and reflect all normal and recurring adjustments, which are, in the opinion of management, necessary to provide a fair presentation of the results of operations and financial position for the interim periods. Such financial statements conform to the presentation reflected in the 2012 Form 10-K. The current interim period reported herein should be read in conjunction with the financial statements and accompanying notes, including Item 8. “Financial Statements and Supplementary Data, Note 2 – Summary of Significant Accounting Policies,” included in the 2012 Form 10-K.
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Significant estimates with regard to these financial statements include the estimate of proved natural gas and oil reserve quantities and the related present value of estimated future net cash flows.
	The unaudited condensed consolidated financial statements of the Company include the accounts of Parent and the consolidated accounts of all of its subsidiaries, including Gastar USA. All significant intercompany accounts and transactions have been eliminated in consolidation.
	The unaudited condensed consolidated financial statements of Gastar USA include the accounts of Gastar USA and the consolidated accounts of all of its subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation.
	Certain reclassifications of prior year balances have been made to conform to the current year presentation; these reclassifications have no impact on net income (loss).
	The results of operations for the three and nine months ended September 30, 2013 are not necessarily indicative of the results that may be expected for the year ending December 31, 2013. In preparing these financial statements, the Company has evaluated events and transactions for potential recognition or disclosure through the date the financial statements were issued and has disclosed certain subsequent events in these condensed consolidated financial statements, as appropriate.
	Recent Accounting Developments
	The following recently issued accounting pronouncement may impact the Company in future periods:
	Income Taxes. In July 2013, the FASB issued an amendment to previously issued guidance regarding the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss or a tax credit carryforward exists. The amendment requires that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented in the financial statements as reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward, except as follows. To the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. The assessment of whether a deferred tax asset is available is based on the unrecognized tax benefit and deferred tax asset that exist at the reporting date and should be made presuming disallowance of the tax position at the reporting date. This amendment does not require new recurring disclosures. This guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. Earlier application is permitted. The Company is currently evaluating the provisions of this amendment.

Property_Plant_And_Equipment

Property, Plant And Equipment	9 Months Ended
	Sep. 30, 2013
Property, Plant and Equipment [Abstract]	'
Property, Plant And Equipment	'
	Property, Plant and Equipment
	The amount capitalized as natural gas and oil properties was incurred for the purchase and development of various properties in the U.S., specifically the states of Texas, Pennsylvania, West Virginia and Oklahoma, as well as the acquisition of properties in Oklahoma. The Company sold substantially all of its East Texas assets on October 2, 2013.
	The following table summarizes the components of unproved properties excluded from amortization for the periods indicated:



		September 30, 2013		December 31, 2012
		(in thousands)
	Unproved properties, excluded from amortization:
	Drilling in progress costs	$	8,821	$	1,902

	Acreage acquisition costs	88,033		62,395

	Capitalized interest	5,484		3,595

	Total unproved properties excluded from amortization	$	102,338	$	67,892


	For the three and nine months ended September 30, 2013, management's evaluation of unproved properties resulted in an impairment. Due to continued lower natural gas prices for dry gas and no current plans to drill or extend leases in Marcellus East, the Company reclassified $98,000 and $8.0 million of unproved properties to proved properties for the three and nine months ended September 30, 2013, respectively, related to acreage in Marcellus East. For the nine months ended September 30, 2012, management's evaluation of unproved properties resulted in an impairment and the Company reclassified $19.1 million of unproved properties to proved properties due to a decline in natural gas prices and the suspension of drilling activity in East Texas.

	The full cost method of accounting for natural gas and oil properties requires a quarterly calculation of a limitation on capitalized costs, often referred to as a full cost ceiling calculation. The ceiling is the present value of estimated future cash flow from proved natural gas, condensate, oil and NGLs reserves reduced by future operating expenses, development expenditures, abandonment costs (net of salvage) to the extent not included in natural gas and oil properties pursuant to authoritative guidance and estimated future income taxes thereon. To the extent that our capitalized costs (net of accumulated depletion and deferred taxes) exceed the ceiling, the excess must be written off to expense. Once incurred, this impairment of natural gas and oil properties is not reversible at a later date even if natural gas and oil prices increase. The ceiling calculation dictates that the trailing 12-month unweighted arithmetic average of the first-day-of-the-month prices and costs in effect are held constant indefinitely. The 12-month unweighted arithmetic average of the first-day-of-the-month prices are adjusted for basis and quality differentials in determining the present value of the reserves. The table below sets forth relevant pricing assumptions utilized in the quarterly ceiling test computations for the respective periods noted before adjustment for basis and quality differentials:



		2013
		Total Impairment		30-Sep		30-Jun		31-Mar
	Henry Hub natural gas price (per MMBtu)			$	3.61	$	3.44	$	2.95

	West Texas Intermediate oil price (per Bbl)			$	91.69	$	88.13	$	89.17

	Impairment recorded (pre-tax) (in thousands)	$	—	$	—	$	—	$	—




		2012
		Total Impairment		30-Sep		30-Jun		31-Mar
	Henry Hub natural gas price (per MMBtu)			$	2.83	$	3.15	$	3.73

	West Texas Intermediate oil price (per Bbl)			$	91.48	$	92.17	$	94.65

	Impairment recorded (pre-tax) (in thousands)	$	150,787	$	78,054	$	72,733	$	—


	Future declines in the 12-month average of natural gas, condensate, oil and NGLs prices could result in the recognition of future ceiling impairments.
	Chesapeake Acquisition
	On March 28, 2013, Gastar USA entered into a Purchase and Sale Agreement by and among Chesapeake Exploration, L.L.C., Arcadia Resources, L.P., Jamestown Resources, L.L.C., Larchmont Resources, L.L.C. (together, the “Chesapeake Parties”) and Gastar USA (the “Chesapeake Purchase Agreement”). Pursuant to the Chesapeake Purchase Agreement, Gastar USA was to acquire approximately 157,000 net acres of Oklahoma oil and gas leasehold interests from the Chesapeake Parties, including production from interests in 206 producing wells located in Oklahoma (the “Chesapeake Assets”). The Chesapeake Purchase Agreement contained customary representations and warranties and covenants, including provisions for indemnification, subject to the limitations described in the Chesapeake Purchase Agreement. On June 7, 2013, the parties to the Chesapeake Purchase Agreement entered into an Amendment to Purchase and Sale Agreement, dated June 7, 2013, in order to revise the description of the properties to be acquired and to evidence the withdrawal of Arcadia Resources, L.P. and Jamestown Resources, L.L.C. from the Chesapeake Purchase Agreement. Pursuant to the Chesapeake Purchase Agreement, as amended, on June 7, 2013, Gastar USA completed the acquisition of the Chesapeake Assets for a final adjusted purchase price of $69.4 million, reflecting adjustment for an acquisition effective date of October 1, 2012.
	Upon completion of the initial purchase price allocation, as of June 7, 2013, the Company reviewed and verified its assessment, including the identification and valuation of assets acquired. The Company accounted for the acquisition as a business combination and therefore, recorded the assets acquired at their estimated acquisition date fair values. The Company included $1.4 million of transaction and integration costs associated with the acquisition and expensed these costs as incurred as general and administrative expenses. The Company utilized relevant market assumptions to determine fair value and allocate the purchase price, such as future commodity prices, projections of estimated natural gas and oil reserves, expectations for future development and operating costs, projections of future rates of production, expected recovery rates and market multiples for similar transactions. Many of the assumptions used are unobservable and as such, represent Level 3 inputs under the fair value hierarchy as described in Note 5, “Fair Value Measurements.” The Company's preliminary assessment of the fair value of the Chesapeake Assets resulted in a fair market valuation of $113.5 million. As a result of incorporating the valuation information into the purchase price allocation, a bargain purchase gain of $43.7 million was recognized in the accompanying condensed consolidated statements of operations. The bargain purchase gain was primarily attributable to the non-strategic nature of the divestiture to the seller, coupled with favorable economic trends in the industry and the geographic region in which the Chesapeake Assets are located. The Company believes the estimates used in the fair market valuation and purchase price allocation are reasonable and that the significant effects of the acquisition are properly reflected. However, the estimates are subject to change as additional information becomes available and is assessed by the Company. Changes to the purchase price allocation and any corresponding change to the bargain purchase gain will be adjusted retrospectively to the period of the acquisition.
	Hunton Joint Venture
	Effective July 1, 2013, Gastar USA's working interest partner in its original AMI in Oklahoma exercised its rights to acquire approximately 12,800 net acres and certain proved properties that Gastar USA acquired pursuant to the Chesapeake Purchase Agreement for a total payment of $12.1 million, of which $133,000 was deemed to be a reimbursement of transaction and integration costs associated with the acquisition and was recorded as a reduction of the Company's general and administrative expense.
	Hunton Divestiture
	On July 2, 2013, Gastar USA entered into a purchase and sale agreement with Newfield Exploration Mid-Continent Inc. (“Newfield”), dated July 2, 2013, pursuant to which Newfield acquired approximately 76,000 net acres of oil and gas leasehold interests in Kingfisher and Canadian Counties, Oklahoma from Gastar USA and Gastar USA acquired approximately 2,260 net acres of Oklahoma oil and gas leasehold interests from Newfield. The transaction closed on August 6, 2013 for a net cash purchase price of approximately $54.0 million, adjusted for an acquisition effective date of May 1, 2013. The Company did not record a gain or loss related to the divestiture as it was not significant to the full cost pool.
	WEHLU Acquisition
	On September 4, 2013, Gastar USA entered into a Purchase and Sale Agreement, dated September 4, 2013, by and among Lime Rock Resources II-A, L.P. and Lime Rock Resources II-C, L.P. (the “Lime Rock Parties”) and Gastar USA (the “WEHLU Purchase Agreement”). Pursuant to the WEHLU Purchase Agreement, Gastar USA will acquire a 98.3% working interest (80.5% net revenue interest) in 24,000 net acres of the West Edmond Hunton Lime Unit (“WEHLU”) located in Kingfisher, Logan and Oklahoma Counties, Oklahoma, for a cash purchase price of $187.5 million, subject to, among other customary adjustments, adjustment for an acquisition effective date of August 1, 2013 (the “WEHLU Acquisition”). The Company paid a deposit of $9.4 million, which is currently recorded as an other asset and will be applied to the purchase price at closing. The closing of the WEHLU Acquisition is subject to satisfaction of customary closing conditions and delivery of the total acquisition purchase price. Gastar USA anticipates the WEHLU Acquisition will close in late November 2013.
	Hilltop Area, East Texas Sale
	On April 19, 2013, Gastar Exploration Texas, LP (“Gastar Texas”) and Gastar USA entered into a Purchase and Sale Agreement by and among Gastar Texas, Gastar USA and Cubic Energy, Inc. (“Cubic Energy”) (the “East Texas Sale Agreement”). Pursuant to the East Texas Sale Agreement, as amended, on October 2, 2013, Cubic Energy acquired from Gastar Texas approximately 31,800 gross (16,300 net) acres of leasehold interests in the Hilltop area of East Texas in Leon and Robertson Counties, Texas, including production from interests in producing wells, for net proceeds of approximately $43.9 million, reflecting adjustment for accounting effective date of January 1, 2013 and other customary adjustments and of which $4.7 million was previously received as a deposit and was accounted for in other liabilities at September 30, 2013. The Company will not record a gain or loss related to the divestiture as it was not significant to the full cost pool.
	Atinum Joint Venture
	In September 2010, Gastar USA entered into a joint venture (the “Atinum Joint Venture”) pursuant to which Gastar USA assigned to an affiliate of Atinum Partners Co., Ltd. (“Atinum”), for $70.0 million in total consideration, an initial 21.43% interest in all of its existing Marcellus Shale assets in West Virginia and Pennsylvania at that date, which consisted of certain undeveloped acreage and a 50% working interest in 16 producing shallow conventional wells and one non-producing vertical Marcellus Shale well (the “Atinum Joint Venture Assets”). In early 2012, Gastar USA made additional assignments to Atinum as a result of which Atinum owns a 50% interest in the Atinum Joint Venture Assets. Subsequent to December 31, 2011, Atinum funds only its 50% share of costs. Effective June 30, 2011, an AMI was established for additional acreage acquisitions in Ohio, New York, Pennsylvania and West Virginia, excluding the counties of Pendleton, Pocahontas, Preston, Randolph and Tucker, West Virginia. Within this AMI, Gastar USA acts as operator and is obligated to offer any future lease acquisitions within the AMI to Atinum on a 50/50 basis, and Atinum will pay Gastar USA on an annual basis an amount equal to 10% of lease bonuses and third party leasing costs up to $20.0 million and 5% of such costs on activities above $20.0 million.
	The Atinum Joint Venture's initial three-year development program called for the partners to drill a minimum of 12 horizontal wells in 2011 and 24 operated horizontal wells in each of 2012 and 2013, respectively, for a total of 60 wells to be drilled. At December 31, 2012, 38 gross operated wells were on production under the Atinum Joint Venture. Due to natural gas price declines, Atinum and Gastar USA agreed to reduce the 2013 minimum wells to be drilled requirement to 19 wells which will result in 57 gross wells on production at December 31, 2013, compared to the 60 gross wells originally agreed upon. As of September 30, 2013, all 57 gross wells were on production as agreed upon.

LongTerm_Debt

Long-Term Debt	9 Months Ended
Long-Term Debt	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Long-Term Debt	'
	Long-Term Debt
	Second Amended and Restated Revolving Credit Facility
	On June 7, 2013, Gastar USA entered into the Second Amended and Restated Credit Agreement, dated as of June 7, 2013, among Gastar USA, Wells Fargo Bank, National Association, as Administrative Agent, Collateral Agent, Swing Line Lender and Issuing Lender and the lenders named therein (the “New Revolving Credit Facility”). The New Revolving Credit Facility provides an initial borrowing base of $50.0 million, with borrowings bearing interest, at Gastar USA's election, at the reference rate or the Eurodollar rate plus an applicable margin. The reference rate is the greater of (i) the rate of interest publicly announced by the administrative agent or (ii) the federal funds rate plus 50 basis points. The applicable interest rate margin varies from 1.0% to 2.0% in the case of borrowings based on the reference rate and from 2.0% to 3.0% in the case of borrowings based on the Eurodollar rate, depending on the utilization percentage in relation to the borrowing base. An annual commitment fee of 0.5% is payable quarterly on the unutilized balance of the borrowing base. The New Revolving Credit Facility has a scheduled maturity of November 14, 2017.
	The New Revolving Credit Facility is guaranteed by all of Gastar USA's current domestic subsidiaries and all future domestic subsidiaries formed during the term of the New Revolving Credit Facility. Borrowings and related guarantees are secured by a first priority lien on all domestic natural gas and oil properties currently owned by or later acquired by Gastar USA and its subsidiaries, excluding de minimus value properties as determined by the lender. The New Revolving Credit Facility is secured by a first priority pledge of the stock of each domestic subsidiary, a first priority interest on all accounts receivable, notes receivable, inventory, contract rights, general intangibles and material property of the issuer and 65% of the stock of each foreign subsidiary of Gastar USA.
	The New Revolving Credit Facility contains various covenants, including among others:

	•	Restrictions on liens, incurrence of other indebtedness without lenders' consent and common stock dividends and other restricted payments;

	•	Maintenance of a minimum consolidated current ratio as of the end of each quarter of not less than 1.0 to 1.0, as adjusted;

	•	Maintenance of a maximum ratio of indebtedness to EBITDA, as of the fiscal quarter ending September 30, 2013, of not greater than 4.25 to 1.0, and for each quarter thereafter, of not greater than 4.0 to 1.0; and

	•	Maintenance of an interest coverage ratio on a rolling four quarters basis, as adjusted, of EBITDA to interest expense, as of the end of each quarter, to be less than 2.5 to 1.0.
	All outstanding amounts owed become due and payable upon the occurrence of certain usual and customary events of default, including among others:

	•	Failure to make payments;

	•	Non-performance of covenants and obligations continuing beyond any applicable grace period; and

	•	The occurrence of a change in control of Gastar USA, as defined in the New Revolving Credit Facility.
	On July 31, 2013, Gastar USA, together with the parties thereto, entered into the Waiver, Agreement and Amendment No. 1 to Second Amended and Restated Credit Agreement (the “First Amendment”). The First Amendment amended the New Revolving Credit Facility to clarify the current ratio covenant calculation.

	On October 18, 2013, Gastar USA, together with the parties thereto, entered into the Agreement and Amendment No. 2 (“Amendment No. 2”) to Second Amended and Restated Credit Agreement, dated as of June 7, 2013. Amendment No. 2 amended the New Revolving Credit Facility to, among other things, (i) increase the aggregate principal amount of 8 5/8% Senior Secured Notes due 2018 permitted to be issued from $200.0 million to $325.0 million, (ii) allow for the issuance by Gastar USA of Series B Preferred Stock and (iii) increase the aggregate amount of cash dividends permitted to be paid to preferred stockholders from $12.5 million to $20.0 million.
	Borrowing base redeterminations are scheduled semi-annually in May and November of each calendar year. Gastar USA and its lenders may request one additional unscheduled redetermination during any six-month period between scheduled redeterminations. At September 30, 2013, the New Revolving Credit Facility had a borrowing base of $50.0 million, with $0 borrowings outstanding and availability of $50.0 million. The next regularly scheduled redetermination is set for November 2013. Future increases in the borrowing base in excess of the $50.0 million are limited to 17.5% of the increase in adjusted consolidated net tangible assets as defined in the Notes agreement (as discussed below in “Senior Secured Notes”).
	At September 30, 2013, Gastar USA was in compliance with all financial covenants under the New Revolving Credit Facility.
	Amended and Restated Revolving Credit Facility
	For the period October 28, 2009 through June 6, 2013, Gastar USA, together with the other parties thereto, was subject to an amended and restated credit facility (the “Old Amended Revolving Credit Facility”). The Old Amended Revolving Credit Facility provided for various borrowing base amounts based on an initial borrowing base of $47.5 million and a final borrowing base of $160.0 million effective March 31, 2013. Borrowings bore interest, at Gastar USA’s election, at the prime rate or LIBO rate plus an applicable margin. The applicable interest rate margin varied from 1.0% to 2.0% in the case of borrowings based on the prime rate and from 2.5% to 3.5% in the case of borrowings based on LIBO rate, depending on the utilization percentage in relation to the borrowing base. An annual commitment fee of 0.5% was payable quarterly based on the unutilized balance of the borrowing base. The Old Amended Revolving Credit Facility had a final scheduled maturity date of September 30, 2015.
	The Old Amended Revolving Credit Facility was guaranteed by Parent (as defined in the Old Amended Revolving Credit Facility) and all of Gastar USA’s current domestic subsidiaries and all future domestic subsidiaries formed during the term of the Old Amended Revolving Credit Facility. Borrowings and related guarantees were secured by a first priority lien on all domestic natural gas and oil properties currently owned by or later acquired by Gastar USA and its subsidiaries, excluding de minimus value properties as determined by the lender. The facility was secured by a first priority pledge of the stock of each domestic subsidiary, a first priority interest on all accounts receivable, notes receivable, inventory, contract rights, general intangibles and material property of the issuer and 65% of the stock of each foreign subsidiary of Gastar USA.
	The Old Amended Revolving Credit Facility contained various covenants, including among others:

	•	Restrictions on liens, incurrence of other indebtedness without lenders' consent and other restricted payments including a restriction on the amount of cash dividends to be paid in aggregate on the Gastar USA Series A Preferred Stock each calendar year, subject to certain available commitment thresholds;

	•	Limitation of hedging volumes with a final limitation of 100% of the proved developed reserves as reflected in Gastar USA's reserve report using hedging other than floors and protective spreads;

	•	Maintenance of a minimum consolidated current ratio as of the end of each quarter of not less than 1.0 to 1.0, as adjusted, except for quarters ending on March 31, 2013 through December 31, 2013 whereby the ratio was reduced to 0.6 to 1.0 and making certain changes in the calculation of current liabilities for such periods to exclude advances from non-operators;

	•	Maintenance of a maximum ratio of indebtedness to EBITDA on a rolling four quarter basis, as adjusted, of not greater than 4.0 to 1.0; and

	•	Maintenance of an interest coverage ratio on a rolling four quarters basis, as adjusted, of EBITDA to interest expense, as of the end of each quarter, to be less than 2.5 to 1.0.
	All outstanding amounts owed became due and payable upon the occurrence of certain usual and customary events of default, including among others:

	•	Failure to make payments;

	•	Non-performance of covenants and obligations continuing beyond any applicable grace period; and

	•	The occurrence of a “Change in Control” (as defined in the Old Amended Revolving Credit Facility) of the Parent.
	The Old Amended Revolving Credit Facility was amended and restated on June 7, 2013.
	Senior Secured Notes
	On May 15, 2013, Gastar USA issued $200.0 million aggregate principal amount of its 8 5/8% Senior Secured Notes due 2018 (the “Notes”) under an indenture (the “Indenture”) by and among Gastar USA, the Guarantors named therein (the “Guarantors”), Wells Fargo Bank, National Association, as Trustee (in such capacity, the “Trustee”) and Collateral Agent (in such capacity, the “Collateral Agent”). The Notes bear interest at a rate of 8.625% per year, payable semiannually in arrears on May 15 and November 15 of each year, beginning on November 15, 2013. The Notes will mature on May 15, 2018.
	In the event of a change of control, as defined in the Indenture, each holder of the Notes will have the right to require Gastar USA to repurchase all or any part of their notes at an offer price in cash equal to 101% of the aggregate principal amount thereof, plus accrued and unpaid interest, if any, to the date of purchase.
	The Notes are fully and unconditionally guaranteed, jointly and severally, on a senior secured basis by each of Gastar USA's material subsidiaries and certain future domestic subsidiaries (the “Guarantees”). The Notes and Guarantees will rank senior in right of payment to all of Gastar USA's and the Guarantors' future subordinated indebtedness and equal in right of payment to all of Gastar USA's and the Guarantors' existing and future senior indebtedness. The Notes and Guarantees also will be effectively senior to Gastar USA's unsecured indebtedness and effectively subordinated to Gastar USA's and Guarantors' under the New Revolving Credit Facility, any other indebtedness secured by a first-priority lien on the same collateral and any other indebtedness secured by assets other than the collateral, in each case to the extent of the value of the assets securing such obligation.
	The Indenture contains covenants that, among other things, limit Gastar USA's ability and the ability of its subsidiaries to:

	•	Transfer or sell assets or use asset sale proceeds;

	•	Pay dividends or make distributions, redeem subordinated debt or make other restricted payments;

	•	Make certain investments; incur or guarantee additional debt or issue preferred equity securities;

	•	Create or incur certain liens on Gastar USA's assets;

	•	Incur dividend or other payment restrictions affecting future restricted subsidiaries;

•	Merge, consolidated or transfer all or substantially all of Gastar USA's assets;

•	Enter into certain transactions with affiliates; and

•	Enter into certain sale and leaseback transactions.
These and other covenants that are contained in the Indenture are subject to important limitations and qualifications that are described in the Indenture.
On May 15, 2013, in connection with the issuance and sale of the Notes, Gastar USA and each of the Guarantors entered into a Registration Rights Agreement (the “Registration Rights Agreement”) with Imperial Capital, LLC, as representative of the initial purchasers. Under the Registration Rights Agreement, Gastar USA has agreed, subject to certain exceptions, to (i) file a registration statement with the SEC with respect to an exchange of the Notes for new notes having terms substantially identical in all material respects to the Notes (except that the exchange notes will not contain terms relating to transfer restrictions), (ii) use its reasonable best efforts to cause the exchange offer registration statement to be declared effective under the Securities Act of 1933, as amended, within 360 days after the issue date of the Notes, (iii) as soon as practicable after the effectiveness of the exchange offer registration statement, offer the exchange notes in exchange for the Notes, and (iv) keep the registered exchange offer open for not less than 30 days (or longer if required by applicable law) after the date of the registered exchange offer is mailed to the holders of the Notes. Gastar USA and the Guarantors also agreed to file a shelf registration statement for the resale of the Notes if an exchange offer cannot be effected within the time period specified above and in other circumstances.
At September 30, 2013, the Notes reflected a balance of $194.8 million, net of unamortized discounts of $5.2 million, on the condensed consolidated balance sheets.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Fair Value Measurements
	The Company’s financial assets and liabilities are measured at fair value on a recurring basis. The Company discloses its recognized non-financial assets and liabilities, such as asset retirement obligations, unproved properties and other property and equipment, at fair value on a non-recurring basis. For non-financial assets and liabilities, the Company is required to disclose information that enables users of its financial statements to assess the inputs used to develop these measurements. The Company assesses its unproved properties for impairment whenever events or circumstances indicate the carrying value of those properties may not be recoverable. The fair value of the unproved properties is measured using an income approach based upon internal estimates of future production levels, current and future prices, drilling and operating costs, discount rates, current drilling plans and favorable and unfavorable drilling activity on the properties being evaluated and/or adjacent properties or estimated market data based on area transactions, which are Level 3 inputs. For the three and nine months ended September 30, 2013, management's evaluation of unproved properties resulted in an impairment. Due to continued lower natural gas prices for dry gas and no current plans to drill or extend leases in Marcellus East, the Company reclassified $8.0 million of unproved properties to proved properties as of September 30, 2013 related to acreage in Marcellus East. For the nine months ended September 30, 2012, the Company reclassified $19.1 million of unproved properties to proved properties due to a decline in natural gas prices and the suspension of drilling activity in East Texas. As no other fair value measurements are required to be recognized on a non-recurring basis at September 30, 2013, no additional disclosures are provided at September 30, 2013.
	As defined in the guidance, fair value is the amount 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 (an exit price). To estimate fair value, the Company utilizes market data or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable. The guidance establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted market prices in active markets for identical assets or liabilities (“Level 1”) and the lowest priority to unobservable inputs (“Level 3”). The three levels of the fair value hierarchy are as follows:

	•	Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. The Company’s cash equivalents consist of short-term, highly liquid investments, which have maturities of 90 days or less, including sweep investments and money market funds.

	•	Level 2 inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the asset or liability, either directly or indirectly through market corroboration, for substantially the full term of the financial instrument.

	•	Level 3 inputs are measured based on prices or valuation models that require inputs that are both significant to the fair value measurement and less observable from objective sources. These inputs may be used with internally developed methodologies or third party broker quotes that result in management’s best estimate of fair value. The Company’s valuation models consider various inputs including (a) quoted forward prices for commodities, (b) time value, (c) volatility factors and (d) current market and contractual prices for the underlying instruments. Significant increases or decreases in any of these inputs in isolation would result in a significantly higher or lower fair value measurement. Level 3 instruments are commodity costless collars, index swaps, basis and fixed price swaps and put and call options to hedge natural gas, oil and NGLs price risk. 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 fair values derived from counterparties and third-party brokers are verified by the Company using publicly available values for relevant NYMEX futures contracts and exchange traded contracts for each derivative settlement location. Although such counterparty and third-party broker quotes are used to assess the fair value of its commodity derivative instruments, the Company does not have access to the specific assumptions used in its counterparties valuation models. Consequently, additional disclosures regarding significant Level 3 unobservable inputs were not provided and the Company does not currently have sufficient corroborating market evidence to support classifying these contracts as Level 2 instruments.
	As required, financial 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 fair value assets and liabilities and their placement within the fair value hierarchy levels. The determination of the fair values below incorporates various factors, including the impact of the counterparty’s non-performance risk with respect to the Company’s financial assets and the Company’s non-performance risk with respect to the Company’s financial liabilities. The Company has not elected to offset the fair value amounts recognized for multiple derivative instruments executed with the same counterparty, but reports them gross on its consolidated balance sheets.
	Transfers between levels are recognized at the end of the reporting period. There were no transfers between levels during the 2013 and 2012 periods.
	The following tables set forth by level within the fair value hierarchy the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2013 and December 31, 2012:


		Fair value as of September 30, 2013
		Level 1				Level 2				Level 3				Total
		(in thousands)
	Assets:
	Cash and cash equivalents	$	21,375			$	—			$	—			$	21,375

	Commodity derivative contracts	—				—				9,658				9,658

	Liabilities:
	Commodity derivative contracts	—				—				(794		)		(794		)

	Total	$	21,375			$	—			$	8,864			$	30,239




		Fair value as of December 31, 2012
		Level 1				Level 2				Level 3				Total
		(in thousands)
	Assets:
	Cash and cash equivalents	$	8,901			$	—			$	—			$	8,901

	Commodity derivative contracts	—				—				9,168				9,168

	Liabilities:
	Commodity derivative contracts	—				—				(2,703		)		(2,703		)

	Total	$	8,901			$	—			$	6,465			$	15,366


	The table below presents a reconciliation of the assets and liabilities classified as Level 3 in the fair value hierarchy for the three and nine months ended September 30, 2013 and 2012. Level 3 instruments presented in the table consist of net derivatives that, in management’s opinion, reflect the assumptions a marketplace participant would have used at September 30, 2013 and 2012.



		Three Months Ended September 30,								Nine Months Ended September 30,
		2013				2012				2013				2012
		(in thousands)
	Balance at beginning of period	$	4,335			$	15,460			$	6,465			$	15,873

	Total gains (losses) (realized or unrealized):
	included in earnings	(5,263		)		(2,045		)		(2,229		)		4,594

	Purchases	9,470				—				9,470				—

	Issuances	—				—				—				—

	Settlements (1)	322				(4,314		)		(4,842		)		(11,366		)

	Transfers in and (out) of Level 3	—				—				—				—

Balance at end of period	$	8,864			$	9,101			$	8,864			$	9,101

The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or (losses) relating to assets still held at September 30, 2013 and 2012	$	(5,004	)		$	(5,403	)		$	(7,156	)		$	(4,123	)
_________________________________

-1	Included in total revenues on the statement of operations.
At September 30, 2013, the estimated fair value of accounts receivable, prepaid expenses, accounts and revenue payables and accrued liabilities approximates their carrying value due to their short-term nature. The estimated fair value of the Company’s long-term debt at September 30, 2013 was $199.3 million based on quoted market prices of the senior secured notes (Level 1).
The Company has consistently applied the valuation techniques discussed above in all periods presented.
The fair value guidance, as amended, establishes that every derivative instrument is to be recorded on the balance sheet as either an asset or liability measured at fair value. See Note 6, “Derivative Instruments and Hedging Activity.”

Derivative_Instruments_And_Hed

Derivative Instruments And Hedging Activity	9 Months Ended
	Sep. 30, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Instruments And Hedging Activity	'
	Derivative Instruments and Hedging Activity
	The Company maintains a commodity price risk management strategy that uses derivative instruments to minimize significant, unanticipated earnings fluctuations that may arise from volatility in commodity prices. The Company uses costless collars, index, basis and fixed price swaps and put and call options to hedge natural gas, condensate, oil and NGLs price risk.
	All derivative contracts are carried at their fair value on the balance sheet and all unrealized gains and losses are recorded in the statement of operations in unrealized hedge gain (loss), while realized gains and losses related to contract settlements are recognized in natural gas, condensate, oil and NGLs revenues. For the three months ended September 30, 2013 and 2012, the Company reported unrealized losses of $5.0 million and $5.4 million, respectively, in the condensed consolidated statement of operations related to the change in the fair value of its commodity derivative instruments. For the nine months ended September 30, 2013 and 2012, the Company reported unrealized losses of $7.2 million and a $4.1 million, respectively, in the condensed consolidated statement of operations related to the change in the fair value of its commodity derivative instruments.
	As of September 30, 2013, the following natural gas derivative transactions were outstanding with the associated notional volumes and weighted average underlying hedge prices:



	Settlement Period		Derivative Instrument		Average			Total of			Base				Floor			Short			Call		Ceiling
					Daily			Notional			Fixed				(Long)			Put			(Long)		(Short)
					Volume			Volume			Price
					(in MMBtus)
	2013		Fixed price swap		5,000			460,000			$	3.65			$	—		$	—		$	—	$	—

	2013		Fixed price swap		1,500			138,000			$	3.85			$	—		$	—		$	—	$	—

	2013		Fixed price swap		1,500			138,000			4				—			—			—		—

	2013		Fixed price swap		3,000			276,000			4.06				—			—			—		—

	2013		Fixed price swap		2,500			230,000			4.05				—			—			—		—

	2013		Fixed price swap		12,663			1,165,000			3.87				—			—			—		—

	2013 (1)		Fixed price swap		2,500			77,500			4.05				—			—			—		—

	2013 (2)		Protective spread		2,500			152,500			4.05				—			3.79			—		—

	2013 (1)		Costless collar		2,500			77,500			—				5			—			—		6.45

	2013 (2)		Short calls		2,500			152,500			—				—			—			—		6.45

	2013		Call spread		2,500			230,000			—				—			—			4.75		5.25

	2013		Basis - HSC (4)		4,000			368,000			(0.11		)		—			—			—		—

	2014		Short calls		2,500			912,500			—				—			—			—		4.59

	2014		Costless three-way collar		10,500			3,832,500			—				3.88			3			—		4.53

	2014		Fixed price swap		11,136			4,064,500			4.06				—			—			—		—

	2015		Fixed price swap		3,000			1,095,000			4				—			—			—		—

	2015		Fixed price swap		2,500			912,500			4.06				—			—			—		—

	2016		Fixed price swap		2,000			732,000			4.11				—			—			—		—

	_______________________________

	-1	For the period July to October 2013.

	-2	For the period November to December 2013.

	-3	East Houston-Katy - Houston Ship Channel.

	As of September 30, 2013, the following crude derivative transactions were outstanding with the associated notional volumes and weighted average underlying hedge prices:


	Settlement Period		Derivative Instrument		Average			Total of			Base				Floor			Short			Ceiling
					Daily			Notional			Fixed				(Long)			Put			(Short)
					Volume (1)			Volume			Price
					(in Bbls)
	2013		Fixed price swap		250			23,000			$	103.95			$	—		$	—		$	—

2013		Fixed price swap		850			78,200			99.77				—			—			—

2013		Fixed price swap		400			36,800			94.86				—			—			—

2013		Fixed price swap		611			56,200			92.8				—			—			—

2013 (2)		Put		1,000			31,000			—				103			—			—

2014 (3)		Fixed price swap		300			54,300			98.05				—			—			—

2014 (3)		Fixed price swap		550			99,550			95.15				—			—			—

2014 (3)		Put		900			162,900			—				98			—			—

2014 (4)		Fixed price swap		200			36,800			93				—			—			—

2014 (4)		Fixed price swap		350			64,400			91.55				—			—			—

2014 (4)		Put		750			138,000			—				93			—			—

2014		Costless collar		200			73,000			—				98			—			98

2014		Fixed price swap		500			182,500			91.1				—			—			—

2014		Fixed price swap		270			98,500			90.77				—			—			—

2014 (5)		Put spread		200			24,400			—				93			73			—

2015		Producer three-way collar		345			126,100			—				85			65			97.8

2015		Producer three-way collar		400			146,000			—				85			70			96.5

2015		Put spread		250			91,250			—				89			69			—

2015 (6)		Producer three-way collar		150			27,150			—				85			65			96.25

2015 (6)		Put spread		700			126,700			—				90			70			—

2015 (7)		Producer three-way collar		50			9,200			—				85			65			96.25

2015 (7)		Put spread		600			110,400			—				87			67			—

2016		Producer three-way collar		275			100,600			—				85			65			95.1

2016		Producer three-way collar		330			120,780			—				80			65			97.35

2016		Put spread		550			201,300			—				85			65			—

2016		Put spread		300			109,800			—				85.5			65.5			—

2017		Producer three-way collar		242			88,150			—				80			60			98.7

2017		Producer three-way collar		280			102,200			—				80			65			97.25

2017		Put spread		500			182,500			—				82			62			—

2018		Put spread		425			103,275			—				80			60			—

_______________________________

-1	Crude volumes hedged include oil, condensate and certain components of our NGLs production.

-2	For the period December 2013.

-3	For the period January to June 2014.

-4	For the period July to December 2014.

-5	For the period September to December 2014.

-6	For the period January to June 2015.

-7	For the period July to December 2015.

As of September 30, 2013, the following NGLs derivative transactions were outstanding with the associated notional volumes and weighted average underlying hedge prices:


Settlement Period		Derivative Instrument		Average			Total of			Base
				Daily			Notional			Fixed
				Volume			Volume			Price
				(in Bbls)
2013		Fixed price swap		150			13,800			$	41.06

2013		Fixed price swap		350			32,200			39.38

As of September 30, 2013, all of the Company’s economic derivative hedge positions were with multinational energy companies or large financial institutions, which are not known to the Company to be in default on their derivative positions. The Company is exposed to credit risk to the extent of non-performance by the counterparties in the derivative contracts discussed above; however, the Company does not anticipate non-performance by such counterparties. None of the Company’s derivative instruments contains credit-risk related contingent features.
In conjunction with certain derivative hedging activity, the Company deferred the payment of certain put premiums for the production month period December 2013 through August 2018. The put premium liabilities become payable monthly as the hedge production month becomes the prompt production month. The Company will begin amortizing the deferred put premium liabilities in December 2013. The following table provides information regarding the deferred put premium liabilities for the periods indicated:


	September 30, 2013				31-Dec-12

Current commodity derivative premium put payable	$	1,819			$	—

Long-term commodity derivative premium payable	7,651				—

Total unamortized put premium liabilities	$	9,470			$	—





Additional Disclosures about Derivative Instruments and Hedging Activities
The tables below provide information on the location and amounts of derivative fair values in the condensed consolidated statement of financial position and derivative gains and losses in the condensed consolidated statement of operations for derivative instruments that are not designated as hedging instruments:



	Fair Values of Derivative Instruments
	Derivative Assets (Liabilities)
			Fair Value
	Balance Sheet Location		September 30, 2013				December 31, 2012
			(in thousands)
Derivatives not designated as hedging instruments
Commodity derivative contracts	Current assets		$	2,259			$	7,799

Commodity derivative contracts	Other assets		7,399				1,369

Commodity derivative contracts	Current liabilities		(794		)		(1,399		)
Commodity derivative contracts	Long-term liabilities		—				(1,304		)

Total derivatives not designated as hedging instruments			$	8,864			$	6,465




	Amount of Gain (Loss) Recognized in Income on Derivatives
			Amount of Gain (Loss)
			Recognized in Income on
			Derivatives For the Three
			Months Ended
	Location of Gain (Loss) Recognized in Income on Derivatives		September 30, 2013				September 30, 2012
			(in thousands)
Derivatives not designated as hedging instruments
Commodity derivative contracts	Natural gas, condensate, oil and NGLs revenues		$	(259	)		$	3,404

Commodity derivative contracts	Unrealized hedge loss		(5,004		)		(5,403		)
Commodity derivative contracts	Interest expense		—				(46		)

Total			$	(5,263	)		$	(2,045	)



	Amount of Gain (Loss) Recognized in Income on Derivatives
			Amount of Gain (Loss)
			Recognized in Income on
			Derivatives For the Nine
			Months Ended
	Location of Gain (Loss) Recognized in Income on Derivatives		September 30, 2013				September 30, 2012
			(in thousands)
Derivatives not designated as hedging instruments
Commodity derivative contracts	Natural gas, condensate, oil and NGLs revenues		$	4,927			$	8,847

Commodity derivative contracts	Unrealized hedge loss		(7,156		)		(4,123		)
Commodity derivative contracts	Interest expense		—				(130		)

Total			$	(2,229	)		$	4,594

Capital_Stock

Capital Stock	9 Months Ended
	Sep. 30, 2013
Stockholders' Equity Note [Abstract]	'
Capital Stock	'
	Capital Stock

	Other Share Issuances
	The following table provides information regarding the issuances and forfeitures of Parent’s common shares pursuant to Parent’s 2006 Long-Term Stock Incentive Plan (the “2006 Plan”) for the periods indicated:



		For the Three Months Ended September 30, 2013		For the Nine Months Ended September 30, 2013
	Other share issuances:
	Restricted common shares granted	41,212		2,219,115

	Restricted common shares vested	123,250		753,779

	Common shares surrendered upon vesting (1)	32,751		222,144

	Common shares forfeited	466,535		512,862

	__________________

	-1	Represents common shares forfeited in connection with the payment of estimated withholding taxes on restricted common shares that vested during the period.

	On June 7, 2012, Parent's shareholders voted to approve the Second Amendment to the 2006 Plan. This amendment, effective June 3, 2012, increased the total number of shares available for issuance under the plan from 6,000,000 shares to 11,000,000 shares. There were 1,931,793 shares available for issuance under the 2006 Plan at September 30, 2013.
	Shares Reserved
	At September 30, 2013, Parent had 909,100 common shares reserved for the exercise of stock options.
	Shares Owned by Chesapeake Energy Corporation
	On March 28, 2013, the Company entered into a Settlement Agreement, dated March 28, 2013, between Chesapeake Exploration, L.L.C. and Chesapeake Energy Corporation (collectively, “Chesapeake”) and the Company, Gastar Exploration Texas, LP and Gastar Exploration Texas, LLC (the “Settlement Agreement”). Pursuant to the Settlement Agreement, the Company settled and resolved all claims of Chesapeake and its subsidiaries against the Company and its subsidiaries made in a previously disclosed lawsuit filed in the U.S. District Court for the Southern District of Texas. In order to effect a mutual full and unconditional release and settlement of all claims made in the lawsuit filed by Chesapeake, the Company paid Chesapeake approximately $10.8 million in cash, approximately $9.8 million of which was paid for the repurchase of 6,781,768 outstanding common shares of Parent held by Chesapeake Energy Corporation upon the closing of the stock repurchase and settlement on June 7, 2013. See Note 13, “Commitments and Contingencies.”
	Gastar USA Common Stock
	Prior to its conversion, as described below, Gastar USA’s articles of incorporation allowed Gastar USA to issue 1,000 shares of common stock, without par value. There were 750 shares issued and outstanding at September 30, 2013 and December 31, 2012, all of which were held by Parent.
	On May 24, 2011, Gastar USA converted from a Michigan corporation to a Delaware corporation (the “Conversion”). Following the Conversion, Gastar USA’s new Delaware certificate of incorporation allows Gastar USA to issue 1,000 shares of common stock, without par value. In connection with the Conversion, the Parent’s 750 shares of common stock in the Michigan corporation were converted to 750 shares of common stock in the new Gastar USA Delaware corporation.
	On October 25, 2013, Gastar USA filed an Amended and Restated Certificate of Incorporation (the “A&R Certificate”) with the Secretary of State of the State of Delaware. Under the A&R Certificate, the capital stock authorized for issuance was increased from 1,000 shares of common stock, without par value, to 275,000,000 shares of common stock, par value $0.001 per share.
	Gastar USA Series A Preferred Stock
	Prior to the Conversion, Gastar USA’s articles of incorporation did not authorize issuance of preferred stock.
	Following the Conversion, Gastar USA’s new Delaware certificate of incorporation allows Gastar USA to issue 10,000,000 shares of preferred stock, with $0.01 par value. The preferred stock may be issued from time to time in one or more series. Gastar USA’s Board of Directors (the “Gastar USA Board”) is authorized to fix the number of shares of any series of preferred stock and to determine the designation of any such series. The Gastar USA Board is also authorized to determine or alter the rights, preferences, privileges and restrictions granted to or imposed upon any wholly unissued series of preferred stock and, within the limits and restrictions stated in any resolution or resolutions of the Gastar USA Board originally fixing the number of shares constituting any series, to increase or decrease (but not below the number of shares of any such series outstanding) the number of shares of any series subsequent to the issues shares of that series.
	For the nine months ended September 30, 2013, Gastar USA sold 6,906 shares of Series A Preferred Stock under its at the market preferred share purchase agreement (the “ATM Agreement”) for net proceeds of $136,000. At September 30, 2013, there were 3,958,160 total shares of Series A Preferred Stock issued and outstanding. Subsequent to September 30, 2013, Gastar USA did not sell any additional shares of Series A Preferred Stock under the ATM Agreement.
	The Series A Preferred Stock is subordinated to all of Gastar USA’s existing and future debt and all future capital stock designated as senior to the Series A Preferred Stock. Parent has entered into a guarantee agreement, whereby it will fully and unconditionally guarantee the payment of dividends that have been declared by the board of directors of Gastar USA, amounts payable upon redemption or liquidation, dissolution or winding up, and any other amounts due with respect to the Series A Preferred Stock, to the extent described in the guarantee agreement. Parent’s obligations with respect to the guarantee will be effectively subordinated to all of its existing and future debt.
	The Series A Preferred Stock cannot be converted into common stock of Gastar USA or the Company, but may be redeemed by Gastar USA, at Gastar USA’s option, on or after June 23, 2014 for $25.00 per share plus any accrued and unpaid dividends or in certain circumstances prior to such date as a result of a change in control. Following a change in control, Gastar USA will have the option to redeem the Series A Preferred Stock, in whole but not in part, within 90 days after the date on which the change in control occurs, for cash at the following prices per share, plus accrued and unpaid dividends (whether or not declared), up to the redemption date:



	Redemption Date	Redemption
		Price
	On or after June 23, 2013 and prior to June 23, 2014	$	25.25

	On or after June 23, 2014	$	25


	Gastar USA pays cumulative dividends on the Series A Preferred Stock at a fixed rate of 8.625% per annum of the $25.00 per share liquidation preference. For the three and nine months ended September 30, 2013, Gastar USA recognized dividend expense of $2.1 million and $6.4 million, respectively.

	Gastar USA Series B Preferred Stock
	On October 25, 2013, Gastar USA filed the A&R Certificate with the Secretary of State of the State of Delaware. Under the A&R Certificate, the capital stock authorized for issuance was increased from 10,000,000 shares of preferred stock, par value $0.01 per share, to 40,000,000 shares of preferred stock, par value $0.01 per share. On October 31, 2013 Gastar USA filed a Certificate of Designation of Rights and Preferences (the “Certificate of Designation”) to its Certificate of Incorporation for the Series B Preferred Stock with the Secretary of State of the State of Delaware with respect to 10,000,000 shares of Series B Preferred Stock.

	On October 29, 2013, Gastar USA announced the pricing of an underwritten public offering of 2,000,000 shares of its 10.75% Series B Cumulative Preferred Stock, par value $0.01 per share and liquidation preference $25.00 per share (the “Series B Preferred Stock”). On November 1, 2013, the underwriters partially exercised their option to purchase additional shares of Series B Preferred Stock and will purchase an additional 140,000 shares of Series B Preferred Stock. The issuance of the 2,140,000 shares of Series B Preferred Stock is expected to close on or about November 5, 2013 with total net proceeds to Gastar USA from the offering expected to be approximately $50.1 million after deducting underwriting commissions and estimated offering expenses.

	The Series B Preferred Stock will rank senior to Gastar USA’s common stock and on parity with its 8.625% Series A Cumulative Preferred Stock with respect to the payment of dividends and distribution of assets upon liquidation, dissolution or winding up. The Series B Preferred Stock will be subordinated to all of Gastar USA’s existing and future debt and all future capital stock designated as senior to the Series B Preferred Stock. The Parent has entered into a guarantee agreement, whereby it will fully and unconditionally guarantee the payment of dividends that have been declared by the board of directors of Gastar USA, amounts payable upon redemption or liquidation, dissolution or winding up, and any other amounts due with respect to the Series B Preferred Stock, to the extent described in the guarantee agreement. Parent’s obligations with respect to the guarantee will be effectively subordinated to all of its existing and future debt.

	Except upon a change in ownership or control, the Series B Preferred Stock may not be redeemed before November 15, 2018, at or after which time it may be redeemed at Gastar USA’s option for $25.00 per share in cash. Following a change in ownership or control, Gastar USA will have the option to redeem the Series B Preferred Stock, in whole but not in part for $25.00 per share in cash, plus accrued and unpaid dividends (whether or not declared), up to, but not including the redemption date. If Gastar USA does not exercise its option to redeem the Series B Preferred Stock upon a change of ownership or control, the holders of the Series B Preferred Stock have the option to convert the shares of Series B Preferred Stock into up to and aggregate of 11.5207 shares of Gastar USA’s common stock per share of Series B Preferred Stock, subject to certain adjustments. If Gastar USA exercises any of its redemption rights relating to shares of Series B Preferred Stock, the holders of Series B Preferred Stock will not have the conversion right described above with respect to the shares of Series B Preferred Stock called for redemption. Notwithstanding any of the foregoing, if a change of ownership or control occurs prior to the consummation of the Reorganization Transactions (as defined in the Certificate of Designation), (i) the holders of Series B Preferred Stock shall not have the conversion right described above and (ii) the dividend rate shall increase to 12.75%.

	There is no mandatory redemption of the Series B Preferred Stock.

Equity_Compensation_PBUs

Equity Compensation - PBUs	9 Months Ended
	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Equity Compensation Plans	'
	Equity Compensation Plans

	Share-Based Compensation Plan
	Pursuant to the 2006 Plan, as amended, the Company's Compensation Committee agreed to allocate a portion of the 2013 long-term incentive grants to executives as performance based units (“PBUs”). The PBUs represent a contractual right to receive shares of Parent's common stock, an amount of cash equal to the fair market value of a share of Parent's common stock, or a combination of shares of Parent's common stock and cash as of the date of settlement based on the number of PBUs to be settled. The settlement of PBUs may range from 0% to 200% of the targeted number of PBUs stated in the agreement contingent upon the achievement of certain share price appreciation targets as compared to a peer group index. The PBUs vest equally and settlement is determined annually over a three year period. Any PBUs not vested at each measurement date will expire.
	Compensation expense associated with PBUs is based on the grant date fair value of a single PBU as determined using a Monte Carlo simulation model which utilizes a stochastic process to create a range of potential future outcomes given a variety of inputs. As the Compensation Committee intends to settle the PBUs with shares of Parent's common stock at each measurement date, the PBU awards are accounted for as equity awards and the expense is calculated on the grant date assuming a 100% target payout and amortized over the life of the PBU award.
	The table below provides a summary of PBUs as of the date indicated:



		PBUs		Fair Value per Unit
	Unvested PBUs at December 31, 2012	—		$	—

	Granted	1,192,889		1.56

	Vested	—		—

	Forfeited	(127,155	)	—

	Unvested PBUs at September 30, 2013	1,065,734		$	1.56

	For the three and nine months ended September 30, 2013, the Company recognized $217,000 and $722,000, respectively, of compensation expense associated with the PBUs granted on January 30, 2013.

Interest_Expense

Interest Expense	9 Months Ended
	Sep. 30, 2013
Interest Expense [Abstract]	'
Interest Expense	'
	Interest Expense
	The following table summarizes the components of interest expense for the periods indicated:



		For the Three Months Ended September 30,						For the Nine Months Ended September 30,
		2013			2012			2013			2012
		(in thousands)
	Interest expense:
	Cash and accrued	$	4,376		$	549		$	8,238		$	1,272

	Amortization of deferred financing costs (1)(2)	340			60			1,790			157

	Capitalized interest	(1,277		)	(579		)	(2,435		)	(1,343		)
	Total interest expense	$	3,439		$	30		$	7,593		$	86

	__________________

	-1	The nine months ended September 30, 2013 includes $1.2 million of deferred financing costs written off as a result of the new Revolving Credit Facility. See Note 4, “Long-Term Debt - Second Amended and Restated Revolving Credit Facility.”

	-2	The three and nine months ended September 30, 2013 includes $221,000 and $330,000, respectively, of debt discount accretion related to the Notes.

Related_Party_Transactions

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2013
Related Party Transactions [Abstract]	'
Related Party Transactions	'
	Related Party Transactions
	Chesapeake Energy Corporation
	Chesapeake Energy Corporation acquired 6,781,768 of Parent’s common shares during 2005 to 2007 in a series of private placement transactions. On March 28, 2013, the Company entered into a Settlement Agreement between Chesapeake Exploration, L.L.C. and Chesapeake Energy Corporation (collectively, “Chesapeake”) and the Company, Gastar Exploration Texas, LP and Gastar Exploration Texas, LLC (the “Settlement Agreement”). Pursuant to the Settlement Agreement, the Company settled and resolved all claims of Chesapeake and its subsidiaries against the Company and its subsidiaries made in a previously disclosed lawsuit filed in the U.S. District Court for the Southern District of Texas. In order to effect a mutual full and unconditional release and settlement of all claims made in the lawsuit filed by Chesapeake, the Company paid Chesapeake approximately $10.8 million in cash, approximately $9.8 million of which was paid for the repurchase of 6,781,768 outstanding common shares of Parent held by Chesapeake upon the closing of the stock repurchase and settlement on June 7, 2013. See Note 7, “Capital Stock - Shares Owned by Chesapeake Energy Corporation.”
	Also on March 28, 2013, the Company entered into the Chesapeake Purchase Agreement, pursuant to which Gastar USA acquired the Chesapeake Assets on June 7, 2013. See Note 3, “Property, Plant and Equipment - Chesapeake Acquisition.”
	As of September 30, 2013, Chesapeake Energy Corporation did not own any of Parent’s outstanding common shares.

Income_Taxes

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	For the three and nine months ended September 30, 2013 and 2012, respectively, the Company did not recognize a current income tax benefit or provision due to the Company being in a net operating loss position for both periods.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings per Share
	In accordance with the provisions of current authoritative guidance, basic earnings or loss per share is computed on the basis of the weighted average number of common shares outstanding during the periods. Diluted earnings or loss per share is computed based upon the weighted average number of common shares outstanding plus the assumed issuance of common shares for all potentially dilutive securities. Diluted amounts are not included in the computation of diluted loss per share, as such would be anti-dilutive.



		For the Three Months Ended September 30,						For the Nine Months Ended September 30,
		2013			2012			2013		2012
		(in thousands, except per share and share data)
	Net income (loss) attributable to Gastar Exploration Ltd.	$	(3,942	)	$	(83,457	)	$	43,308	$	(163,802	)


	Weighted average common shares outstanding - basic	57,359,357			63,601,645			61,159,117		63,494,224

	Incremental shares from unvested restricted shares	—			—			2,565,888		—

	Incremental shares from outstanding PBUs	—			—			246,033		—

	Weighted average common shares outstanding - diluted	57,359,357			63,601,645			63,971,038		63,494,224


	Net income (loss) per common share attributable to Gastar Exploration Ltd. Common Shareholders:
	Basic	$	(0.07	)	$	(1.31	)	$	0.71	$	(2.58	)

	Diluted	$	(0.07	)	$	(1.31	)	$	0.68	$	(2.58	)

	Common shares excluded from denominator as anti-dilutive:
	Unvested restricted shares	—			1,878,355			41,212		1,654,439

	Stock options	756,200			979,725			919,100		926,271

	Total	756,200			2,858,080			960,312		2,580,710

Commitments_And_Contingencies

Commitments And Contingencies	9 Months Ended
Commitments And Contingencies	Sep. 30, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Commitments And Contingencies	'
	Commitments and Contingencies
	Litigation
	Chesapeake Exploration L.L.C. (“Chesapeake Exploration”) and Chesapeake Energy Corp. (“Chesapeake Energy”) v. Gastar Exploration Ltd., Gastar Exploration Texas, LP, and Gastar Exploration Texas, LLC (No. 4:12-cv-2922), United States District Court for the Southern District of Texas, Houston Division. This lawsuit, filed on October 1, 2012, re-asserted the same claims for rescission of the November 2005 Agreements (as defined below) and for recovery of amounts paid under those agreements that Chesapeake Exploration and Chesapeake Energy (collectively, “Chesapeake”) previously asserted in the cross-action filed against the Company in the Navasota litigation described below, as previously disclosed in the Company's filings. In March 2011, Chesapeake dismissed its cross-claims against the Company in the Navasota litigation, without prejudice to their re-filing. In the new lawsuit, Chesapeake re-asserted those claims, seeking rescission of (a) a Purchase and Sale and Exploration and Development Agreement between the Company and Chesapeake Exploration Limited Partnership (the “Purchase and Sale Agreement”), relating to properties in the Hilltop Prospect in Texas, (b) an Exploration and Development Agreement between the Company and Chesapeake Exploration Limited Partnership, (c) a Common Share Purchase Agreement between the Company and Chesapeake Energy, and (d) a Registration Rights Agreement between the Company and Chesapeake Energy, all effective as of November 4, 2005 (collectively, “the November 2005 Agreements”), based on an alleged “mutual mistake” and alleged failure of consideration. Chesapeake alleged that the parties to the November 2005 Agreements believed that the Gastar defendants had the right to convey to Chesapeake Exploration the properties that were the subject of the Purchase and Sale Agreement, notwithstanding the exercise by Navasota Resources LP (“Navasota”) of a preferential right to purchase the interest in the Hilltop Prospect properties. The dispute over the validity of Navasota's exercise of its preferential right to purchase was the subject of litigation filed by Navasota prior to the execution of the November 2005 Agreements. Chesapeake claims that the Texas Court of Appeals' subsequent ruling in that litigation upholding the validity of Navasota's exercise of the preferential right to purchase established that there was a mutual mistake of fact and a failure of consideration with regard to the November 2005 Agreements. In the alternative, Chesapeake claimed that the Gastar defendants had been unjustly enriched at the expense of Chesapeake by the funds paid by Chesapeake to the Gastar defendants. In their complaint filed in the lawsuit, Chesapeake offered to return Parent's common shares purchased pursuant to the Common Stock Purchase Agreement, and sought restitution from the Gastar defendants of the net amount of approximately $101.4 million, which included the $76.0 million that Chesapeake Energy paid for Parent's common shares (now 5,430,329 shares after a 1:5 stock split) that Chesapeake Energy purchased in 2005 and now seeks to return. In a motion to compel arbitration filed by Chesapeake on October 24, 2012, Chesapeake asked the court to order arbitration of the claims asserted in the complaint pursuant to an arbitration clause in the Common Share Purchase Agreement.
	The Gastar defendants responded to the lawsuit by filing a motion to dismiss, contending that the claims failed as a matter of law. Specifically, the Gastar defendants contended in the motion to dismiss that all facts relating to the Navasota claim were fully known to the parties at the time of execution of the November 2005 Agreements, and the parties expressly agreed in the Purchase and Sale Agreement that Chesapeake Exploration would take title to the properties subject to Navasota's claim and would convey the properties to Navasota in the event Navasota prevailed in the litigation, precluding Chesapeake's claims for rescission of the November 2005 Agreements. For the same reasons, the Gastar defendants also contended in the motion to dismiss that Chesapeake received all of the consideration that the November 2005 Agreements called for and that there was no failure of consideration. With regard to Chesapeake's alternative unjust enrichment claim, the Gastar defendants contended in the motion to dismiss that it is barred by the two-year statute of limitations and that in any event, it failed for a variety of reasons, including the fact that the parties' agreements address the subject matter of the dispute (precluding a claim for unjust enrichment) and the fact that the Gastar defendants were not unjustly enriched by Chesapeake Exploration's payment of the share of costs attributable to an interest in the properties that was not owned by the Gastar defendants. The Gastar defendants also contended in their response to the motion to compel arbitration that Chesapeake's claims are not subject to arbitration and that the claims should be resolved on the merits by the federal court in which Chesapeake filed the lawsuit.
	On March 28, 2013, the Company entered into a Settlement Agreement between Chesapeake and the Gastar defendants (the “Settlement Agreement”). Pursuant to the Settlement Agreement, the Gastar defendants settled and resolved all claims of Chesapeake and its subsidiaries against the Company and its subsidiaries made in the Chesapeake lawsuit. In order to affect a mutual full and unconditional release and settlement of all claims made in the lawsuit filed by Chesapeake, the Company paid Chesapeake approximately $10.8 million in cash, approximately $9.8 million of which was paid for the repurchase of 6,781,768 outstanding common shares of the Company currently held by Chesapeake Energy Corporation.
	On the same day that the Company entered into the Settlement Agreement, Gastar USA entered into an agreement for the acquisition of certain properties from Chesapeake. The closing of the proposed property acquisition, stock repurchase and settlement for an adjusted aggregate cash payment of $80.0 million, comprised of approximately $69.4 million in property acquisition costs (subject to adjustment for an acquisition effective date of October 1, 2012), stock repurchase price of approximately $9.8 million and an additional $1.0 million for litigation settlement occurred on June 7, 2013. On March 31, 2013, following notification to the Court regarding the execution of the settlement agreement, the Court in the Chesapeake lawsuit entered an order of dismissal, without prejudice to the right of counsel of record to move for reinstatement of the case within 90 days in the event the settlement is not consummated.
	The acquisition transaction closed on June 7, 2013, and the payments described above were made as provided in the Settlement Agreement and the agreement for acquisition of properties from Chesapeake. Thereafter, the parties to the Chesapeake lawsuit filed a stipulation of dismissal of prejudice, and on June 11, 2013, the court entered an order dismissing the case with prejudice.
	Gastar Exploration USA, Inc., et al v. Williams Ohio Valley Midstream LLC (American Arbitration Association Matter No. 70-198-Y-00461-13). On July 16, 2013, Gastar USA and two similarly situated co-claimants initiated an arbitration proceeding against Williams Ohio Valley Midstream LLC (“Williams OVM”). The claimants allege that Williams OVM has breached various agreements relating to the gathering, processing and marketing of natural gas, NGLs and condensate produced from properties that are owned in part by Gastar USA in the Marcellus Shale in Marshall and Wetzel Counties, West Virginia, and request that an Arbitration Panel assess an unspecified amount of damages against Williams OVM for, among other claims, failure to timely construct certain gathering and processing facilities, maximize the net value of produced condensation, and fractionate and purchase NGLs as provided in the agreements. On August 7, 2013, Williams OVM filed an answering statement and counterclaim for damages in excess of $612,000 in the arbitration matter. The arbitration has been scheduled for a final hearing in October 2014. Gastar USA intends to vigorously pursue its rights in the arbitration matter against Williams OVM.
	Gastar Exploration Ltd vs. U.S. Specialty Ins. Co. and Axis Ins. Co. (Cause No.2010-11236) District Court of Harris County, Texas 190th Judicial District. On February 19, 2010, the Company filed a lawsuit claiming that the Company was due reimbursement of qualifying claims related to the settlement and associated legal defense costs under the Company's directors and officers liability insurance policies related to the ClassicStar Mare Lease Litigation settled on December 17, 2010 for $21.2 million. The combined coverage limits under the directors and officers liability coverage is $20.0 million. The District Court granted the underwriters' summary judgment request by a ruling dated January 4, 2012. The Company appealed the District Court ruling and on July 15, 2013, the Fourteenth Court of Appeals of Texas reversed the summary judgment ruling granted against the Company on the basis of the policies' prior-and-pending litigation endorsement and remanded the case for further proceedings in the District Court. The District Court proceedings will include, but not be limited to, a determination of whether the Company's claims are securities claims covered by the insuring agreements. The insurers have filed a motion for reconsideration in the Court of Appeals. The insurers may seek discretionary review from the Texas Supreme Court if they do not succeed with their motion for rehearing.
	The Company has been expensing legal costs on these proceedings as they are incurred.
	The Company is party to various legal proceedings arising in the normal course of business. The ultimate outcome of each of these matters cannot be absolutely determined, and the liability the Company may ultimately incur with respect to any one of these matters in the event of a negative outcome may be in excess of amounts currently accrued for with respect to such matters. Net of available insurance and performance of contractual defense and indemnity obligations, where applicable, management does not believe any such matters will have a material adverse effect on the Company’s financial position, results of operations or cash flows.

Statement_Of_Cash_Flows_Supple

Statement Of Cash Flows - Supplemental Information	9 Months Ended
	Sep. 30, 2013
Supplemental Cash Flow Information [Abstract]	'
Statement Of Cash Flows - Supplemental Information	'
	Statement of Cash Flows – Supplemental Information
	The following is a summary of the supplemental cash paid and non-cash transactions for the periods indicated:



		For the Nine Months Ended September 30,
		2013			2012
		(in thousands)
	Cash paid for interest	$	1,920		$	1,280

	Non-cash transactions:
	Capital expenditures excluded from accounts payable and accrued drilling costs	(8,335		)	724

	Capital expenditures excluded from prepaid expenses	—			99

	Asset retirement obligation included in natural gas and oil properties	1,795			229

	Asset retirement obligation assigned to operator	(362		)	(2,099		)
	Application of advances to operators	14,443			5,848

	Other	61			—

Summary_Of_Significant_Account1

Summary Of Significant Accounting Policies (Policies)	9 Months Ended
Summary Of Significant Accounting Policies (Policies)	Sep. 30, 2013
Accounting Policies [Abstract]	'
Basis of Accounting, Policy	'
Basis of Accounting, Policy	The unaudited interim condensed consolidated financial statements of the Company and Gastar USA included herein are stated in U.S. dollars and were prepared from the records of the Company and Gastar USA by management in accordance with U.S. GAAP applicable to interim financial statements and reflect all normal and recurring adjustments, which are, in the opinion of management, necessary to provide a fair presentation of the results of operations and financial position for the interim periods. Such financial statements conform to the presentation reflected in the 2012 Form 10-K. The current interim period reported herein should be read in conjunction with the financial statements and accompanying notes, including Item 8. “Financial Statements and Supplementary Data, Note 2 – Summary of Significant Accounting Policies,” included in the 2012 Form 10-K.

Property_Plant_And_Equipment_T

Property, Plant And Equipment (Tables)	9 Months Ended
	Sep. 30, 2013
Property, Plant and Equipment [Abstract]	'
Schedule of Capitalized Costs of Unproved Properties Excluded from Amortization	'
	The following table summarizes the components of unproved properties excluded from amortization for the periods indicated:



		September 30, 2013		December 31, 2012
		(in thousands)
	Unproved properties, excluded from amortization:
	Drilling in progress costs	$	8,821	$	1,902

	Acreage acquisition costs	88,033		62,395

	Capitalized interest	5,484		3,595

	Total unproved properties excluded from amortization	$	102,338	$	67,892

Schedule Of Relevant Assumptions Used In Ceiling Test Computations	'
	The table below sets forth relevant pricing assumptions utilized in the quarterly ceiling test computations for the respective periods noted before adjustment for basis and quality differentials:



		2013
		Total Impairment		30-Sep		30-Jun		31-Mar
	Henry Hub natural gas price (per MMBtu)			$	3.61	$	3.44	$	2.95

	West Texas Intermediate oil price (per Bbl)			$	91.69	$	88.13	$	89.17

	Impairment recorded (pre-tax) (in thousands)	$	—	$	—	$	—	$	—




		2012
		Total Impairment		30-Sep		30-Jun		31-Mar
	Henry Hub natural gas price (per MMBtu)			$	2.83	$	3.15	$	3.73

	West Texas Intermediate oil price (per Bbl)			$	91.48	$	92.17	$	94.65

	Impairment recorded (pre-tax) (in thousands)	$	150,787	$	78,054	$	72,733	$	—

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements, Recurring and Nonrecurring	'
	The following tables set forth by level within the fair value hierarchy the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2013 and December 31, 2012:


		Fair value as of September 30, 2013
		Level 1			Level 2			Level 3			Total
		(in thousands)
	Assets:
	Cash and cash equivalents	$	21,375		$	—		$	—		$	21,375

	Commodity derivative contracts	—			—			9,658			9,658

	Liabilities:
	Commodity derivative contracts	—			—			(794		)	(794		)

	Total	$	21,375		$	—		$	8,864		$	30,239




		Fair value as of December 31, 2012
		Level 1			Level 2			Level 3			Total
		(in thousands)
	Assets:
	Cash and cash equivalents	$	8,901		$	—		$	—		$	8,901

	Commodity derivative contracts	—			—			9,168			9,168

	Liabilities:
	Commodity derivative contracts	—			—			(2,703		)	(2,703		)

	Total	$	8,901		$	—		$	6,465		$	15,366

Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation	'
	The table below presents a reconciliation of the assets and liabilities classified as Level 3 in the fair value hierarchy for the three and nine months ended September 30, 2013 and 2012. Level 3 instruments presented in the table consist of net derivatives that, in management’s opinion, reflect the assumptions a marketplace participant would have used at September 30, 2013 and 2012.



		Three Months Ended September 30,						Nine Months Ended September 30,
		2013			2012			2013			2012
		(in thousands)
	Balance at beginning of period	$	4,335		$	15,460		$	6,465		$	15,873

	Total gains (losses) (realized or unrealized):
	included in earnings	(5,263		)	(2,045		)	(2,229		)	4,594

	Purchases	9,470			—			9,470			—

	Issuances	—			—			—			—

	Settlements (1)	322			(4,314		)	(4,842		)	(11,366		)

	Transfers in and (out) of Level 3	—			—			—			—

	Balance at end of period	$	8,864		$	9,101		$	8,864		$	9,101

	The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or (losses) relating to assets still held at September 30, 2013 and 2012	$	(5,004	)	$	(5,403	)	$	(7,156	)	$	(4,123	)
	_________________________________

	-1	Included in total revenues on the statement of operations.

Derivative_Instruments_And_Hed1

Derivative Instruments And Hedging Activity (Tables)	9 Months Ended
	Sep. 30, 2013
Derivative [Line Items]	'
Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location	'
	The following table provides information regarding the deferred put premium liabilities for the periods indicated:


		September 30, 2013				31-Dec-12

	Current commodity derivative premium put payable	$	1,819			$	—

	Long-term commodity derivative premium payable	7,651				—

	Total unamortized put premium liabilities	$	9,470			$	—

Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location	'
	The tables below provide information on the location and amounts of derivative fair values in the condensed consolidated statement of financial position and derivative gains and losses in the condensed consolidated statement of operations for derivative instruments that are not designated as hedging instruments:



		Fair Values of Derivative Instruments
		Derivative Assets (Liabilities)
				Fair Value
		Balance Sheet Location		September 30, 2013				December 31, 2012
				(in thousands)
	Derivatives not designated as hedging instruments
	Commodity derivative contracts	Current assets		$	2,259			$	7,799

	Commodity derivative contracts	Other assets		7,399				1,369

	Commodity derivative contracts	Current liabilities		(794		)		(1,399		)
	Commodity derivative contracts	Long-term liabilities		—				(1,304		)

	Total derivatives not designated as hedging instruments			$	8,864			$	6,465




		Amount of Gain (Loss) Recognized in Income on Derivatives
				Amount of Gain (Loss)
				Recognized in Income on
				Derivatives For the Three
				Months Ended
		Location of Gain (Loss) Recognized in Income on Derivatives		September 30, 2013				September 30, 2012
				(in thousands)
	Derivatives not designated as hedging instruments
	Commodity derivative contracts	Natural gas, condensate, oil and NGLs revenues		$	(259	)		$	3,404

	Commodity derivative contracts	Unrealized hedge loss		(5,004		)		(5,403		)
	Commodity derivative contracts	Interest expense		—				(46		)

	Total			$	(5,263	)		$	(2,045	)



		Amount of Gain (Loss) Recognized in Income on Derivatives
				Amount of Gain (Loss)
				Recognized in Income on
				Derivatives For the Nine
				Months Ended
		Location of Gain (Loss) Recognized in Income on Derivatives		September 30, 2013				September 30, 2012
				(in thousands)
	Derivatives not designated as hedging instruments
	Commodity derivative contracts	Natural gas, condensate, oil and NGLs revenues		$	4,927			$	8,847

	Commodity derivative contracts	Unrealized hedge loss		(7,156		)		(4,123		)
	Commodity derivative contracts	Interest expense		—				(130		)

	Total			$	(2,229	)		$	4,594


Natural Gas	'
Derivative [Line Items]	'
Schedule of Notional Amounts of Outstanding Derivative Positions	'
	As of September 30, 2013, the following natural gas derivative transactions were outstanding with the associated notional volumes and weighted average underlying hedge prices:



	Settlement Period		Derivative Instrument		Average			Total of			Base				Floor			Short			Call		Ceiling
					Daily			Notional			Fixed				(Long)			Put			(Long)		(Short)
					Volume			Volume			Price
					(in MMBtus)
	2013		Fixed price swap		5,000			460,000			$	3.65			$	—		$	—		$	—	$	—

	2013		Fixed price swap		1,500			138,000			$	3.85			$	—		$	—		$	—	$	—

	2013		Fixed price swap		1,500			138,000			4				—			—			—		—

	2013		Fixed price swap		3,000			276,000			4.06				—			—			—		—

	2013		Fixed price swap		2,500			230,000			4.05				—			—			—		—

	2013		Fixed price swap		12,663			1,165,000			3.87				—			—			—		—

	2013 (1)		Fixed price swap		2,500			77,500			4.05				—			—			—		—

	2013 (2)		Protective spread		2,500			152,500			4.05				—			3.79			—		—

	2013 (1)		Costless collar		2,500			77,500			—				5			—			—		6.45

	2013 (2)		Short calls		2,500			152,500			—				—			—			—		6.45

	2013		Call spread		2,500			230,000			—				—			—			4.75		5.25

	2013		Basis - HSC (4)		4,000			368,000			(0.11		)		—			—			—		—

	2014		Short calls		2,500			912,500			—				—			—			—		4.59

	2014		Costless three-way collar		10,500			3,832,500			—				3.88			3			—		4.53

	2014		Fixed price swap		11,136			4,064,500			4.06				—			—			—		—

	2015		Fixed price swap		3,000			1,095,000			4				—			—			—		—

	2015		Fixed price swap		2,500			912,500			4.06				—			—			—		—

	2016		Fixed price swap		2,000			732,000			4.11				—			—			—		—

	_______________________________

	-1	For the period July to October 2013.

	-2	For the period November to December 2013.

	-3	East Houston-Katy - Houston Ship Channel
Crude Oil	'
Derivative [Line Items]	'
Schedule of Notional Amounts of Outstanding Derivative Positions	'
	As of September 30, 2013, the following crude derivative transactions were outstanding with the associated notional volumes and weighted average underlying hedge prices:


	Settlement Period		Derivative Instrument		Average			Total of			Base				Floor			Short			Ceiling
					Daily			Notional			Fixed				(Long)			Put			(Short)
					Volume (1)			Volume			Price
					(in Bbls)
	2013		Fixed price swap		250			23,000			$	103.95			$	—		$	—		$	—

	2013		Fixed price swap		850			78,200			99.77				—			—			—

	2013		Fixed price swap		400			36,800			94.86				—			—			—

	2013		Fixed price swap		611			56,200			92.8				—			—			—

	2013 (2)		Put		1,000			31,000			—				103			—			—

	2014 (3)		Fixed price swap		300			54,300			98.05				—			—			—

	2014 (3)		Fixed price swap		550			99,550			95.15				—			—			—

	2014 (3)		Put		900			162,900			—				98			—			—

	2014 (4)		Fixed price swap		200			36,800			93				—			—			—

	2014 (4)		Fixed price swap		350			64,400			91.55				—			—			—

	2014 (4)		Put		750			138,000			—				93			—			—

	2014		Costless collar		200			73,000			—				98			—			98

	2014		Fixed price swap		500			182,500			91.1				—			—			—

	2014		Fixed price swap		270			98,500			90.77				—			—			—

	2014 (5)		Put spread		200			24,400			—				93			73			—

	2015		Producer three-way collar		345			126,100			—				85			65			97.8

	2015		Producer three-way collar		400			146,000			—				85			70			96.5

	2015		Put spread		250			91,250			—				89			69			—

	2015 (6)		Producer three-way collar		150			27,150			—				85			65			96.25

	2015 (6)		Put spread		700			126,700			—				90			70			—

	2015 (7)		Producer three-way collar		50			9,200			—				85			65			96.25

	2015 (7)		Put spread		600			110,400			—				87			67			—

	2016		Producer three-way collar		275			100,600			—				85			65			95.1

	2016		Producer three-way collar		330			120,780			—				80			65			97.35

	2016		Put spread		550			201,300			—				85			65			—

	2016		Put spread		300			109,800			—				85.5			65.5			—

	2017		Producer three-way collar		242			88,150			—				80			60			98.7

	2017		Producer three-way collar		280			102,200			—				80			65			97.25

2017		Put spread		500			182,500			—				82			62			—

2018		Put spread		425			103,275			—				80			60			—

_______________________________

-1	Crude volumes hedged include oil, condensate and certain components of our NGLs production.

-2	For the period December 2013.

-3	For the period January to June 2014.

-4	For the period July to December 2014.

-5	For the period September to December 2014.

-6	For the period January to June 2015.

-7	For the period July to December 2015.
Natural Gas Liquids	'
Derivative [Line Items]	'
Schedule of Notional Amounts of Outstanding Derivative Positions	'
	As of September 30, 2013, the following NGLs derivative transactions were outstanding with the associated notional volumes and weighted average underlying hedge prices:


	Settlement Period		Derivative Instrument		Average			Total of			Base
					Daily			Notional			Fixed
					Volume			Volume			Price
					(in Bbls)
	2013		Fixed price swap		150			13,800			$	41.06

	2013		Fixed price swap		350			32,200			39.38

Capital_Stock_Tables

Capital Stock (Tables)	9 Months Ended
	Sep. 30, 2013
Stockholders' Equity Note [Abstract]	'
Schedule of Issuances And Forfeitures Of Common Shares	'
	The following table provides information regarding the issuances and forfeitures of Parent’s common shares pursuant to Parent’s 2006 Long-Term Stock Incentive Plan (the “2006 Plan”) for the periods indicated:



		For the Three Months Ended September 30, 2013		For the Nine Months Ended September 30, 2013
	Other share issuances:
	Restricted common shares granted	41,212		2,219,115

	Restricted common shares vested	123,250		753,779

	Common shares surrendered upon vesting (1)	32,751		222,144

	Common shares forfeited	466,535		512,862

	__________________

	-1	Represents common shares forfeited in connection with the payment of estimated withholding taxes on restricted common shares that vested during the period.
Schedule of Auction Market Preferred Securities by Stock Series	'
	Following a change in control, Gastar USA will have the option to redeem the Series A Preferred Stock, in whole but not in part, within 90 days after the date on which the change in control occurs, for cash at the following prices per share, plus accrued and unpaid dividends (whether or not declared), up to the redemption date:



	Redemption Date	Redemption
		Price
	On or after June 23, 2013 and prior to June 23, 2014	$	25.25

	On or after June 23, 2014	$	25

Equity_Compensation_PBUs_Table

Equity Compensation - PBUs (Tables)	9 Months Ended
	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Schedule of Share-based Compensation, Stock Options, Activity	'
	The table below provides a summary of PBUs as of the date indicated:



		PBUs		Fair Value per Unit
	Unvested PBUs at December 31, 2012	—		$	—

	Granted	1,192,889		1.56

	Vested	—		—

	Forfeited	(127,155	)	—

	Unvested PBUs at September 30, 2013	1,065,734		$	1.56

Interest_Expense_Tables

Interest Expense (Tables)	9 Months Ended
	Sep. 30, 2013
Interest Expense [Abstract]	'
Schedule Of Components Of Interest Expense	'
	The following table summarizes the components of interest expense for the periods indicated:



		For the Three Months Ended September 30,						For the Nine Months Ended September 30,
		2013			2012			2013			2012
		(in thousands)
	Interest expense:
	Cash and accrued	$	4,376		$	549		$	8,238		$	1,272

	Amortization of deferred financing costs (1)(2)	340			60			1,790			157

	Capitalized interest	(1,277		)	(579		)	(2,435		)	(1,343		)
	Total interest expense	$	3,439		$	30		$	7,593		$	86

	__________________

	-1	The nine months ended September 30, 2013 includes $1.2 million of deferred financing costs written off as a result of the new Revolving Credit Facility. See Note 4, “Long-Term Debt - Second Amended and Restated Revolving Credit Facility.”

	-2	The three and nine months ended September 30, 2013 includes $221,000 and $330,000, respectively, of debt discount accretion related to the Notes.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Schedule of Earnings Per Share, Basic and Diluted	'


		For the Three Months Ended September 30,						For the Nine Months Ended September 30,
		2013			2012			2013		2012
		(in thousands, except per share and share data)
	Net income (loss) attributable to Gastar Exploration Ltd.	$	(3,942	)	$	(83,457	)	$	43,308	$	(163,802	)


	Weighted average common shares outstanding - basic	57,359,357			63,601,645			61,159,117		63,494,224

	Incremental shares from unvested restricted shares	—			—			2,565,888		—

	Incremental shares from outstanding PBUs	—			—			246,033		—

	Weighted average common shares outstanding - diluted	57,359,357			63,601,645			63,971,038		63,494,224


	Net income (loss) per common share attributable to Gastar Exploration Ltd. Common Shareholders:
	Basic	$	(0.07	)	$	(1.31	)	$	0.71	$	(2.58	)

	Diluted	$	(0.07	)	$	(1.31	)	$	0.68	$	(2.58	)

	Common shares excluded from denominator as anti-dilutive:
	Unvested restricted shares	—			1,878,355			41,212		1,654,439

	Stock options	756,200			979,725			919,100		926,271

	Total	756,200			2,858,080			960,312		2,580,710

Statement_Of_Cash_Flows_Supple1

Statement Of Cash Flows - Supplemental Information (Tables)	9 Months Ended
	Sep. 30, 2013
Supplemental Cash Flow Information [Abstract]	'
Statement Of Cash Flows Supplemental Information	'
	The following is a summary of the supplemental cash paid and non-cash transactions for the periods indicated:



		For the Nine Months Ended September 30,
		2013			2012
		(in thousands)
	Cash paid for interest	$	1,920		$	1,280

	Non-cash transactions:
	Capital expenditures excluded from accounts payable and accrued drilling costs	(8,335		)	724

	Capital expenditures excluded from prepaid expenses	—			99

	Asset retirement obligation included in natural gas and oil properties	1,795			229

	Asset retirement obligation assigned to operator	(362		)	(2,099		)
	Application of advances to operators	14,443			5,848

	Other	61			—

Property_Plant_And_Equipment_N

Property, Plant And Equipment (Narrative) (Details) (USD $)

3 Months Ended

9 Months Ended

0 Months Ended

1 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

0 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Jul. 04, 2013

Jun. 07, 2013

Mar. 28, 2013

Jul. 04, 2013

Sep. 04, 2013

Apr. 19, 2013

Jun. 29, 2013

Jul. 02, 2013

Sep. 30, 2010

Sep. 30, 2013

Dec. 31, 2011

Dec. 31, 2012

Mar. 31, 2012

Sep. 30, 2013

Jul. 11, 2013

Jun. 07, 2013

Gastar Exploration USA

Hunton Divestiture

Chesapeake Assets

Oklahoma Oil and Gas Leasehold Interests

WEHLU Purchase Agreement

East Texas

Hunton Joint Venture

Atinum Joint Venture

Other assets

General and administrative expenses

acre

well

Maximum

WEHLU Purchase Agreement

Chesapeake Assets

well

Property, Plant and Equipment [Line Items]

Amount reclassifed from unproved to proved properties

$98,000

$8,000,000

$19,100,000

Net acres (acres)

76,000

157,000

2,260

24,000

16,300

12,800

Productive conventional wells (wells)

206

Adjusted purchase price

69,400,000

187,500,000

70,000,000

Transaction and integration costs

133,000

1,400,000

Fair market valuation

113,500,000

Bargain purchase gain

43,712,000

43,700,000

Payments to acquire oil and gas property

12,100,000

Total consideration

54,000,000

Working interest in wells (percentage)

98.30%

50.00%

Net revenue interest in wells

80.50%

Deposit previously paid

9,400,000

Gross acres (acres)

31,800

Proceeds from sale of natural gas and oil properties

70,708,000

43,900,000

Security deposit received

$4,700,000

Initial interest in Marcellus Shale Assets (percentage)

21.43%

Non productive number of wells (wells)

Atinum ownership interest in Atinum Joint Venture Assets (percentage)

50.00%

Joint interest share of drilling completion and infrastructure costs (percentage)

50.00%

Percentage of reimbursements for lease bonuses and third party lease costs up to 20 million (percentage)

10.00%

Percentage of lease operating expenses covered (percentage)

5.00%

Term of development program

'3 years

Minimum wells to be drilled (wells)

Required exploratroy wells drilled net productive to be drilled in current fiscal year (wells)

Total wells to be drilled (wells)

Gross operated wells on production (wells)

Total reduction in 2013 minimum wells to be drilled (wells)

Total revised gross wells on production in 2013 (wells)

Property_Plant_And_Equipment_S

Property, Plant And Equipment (Schedule of Capitalized Costs of Unproved Properties Excluded from Amortization) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Unproved properties, excluded from amortization:	'	'
Drilling in progress costs	$8,821	$1,902
Acreage acquisition costs	88,033	62,395
Capitalized interest	5,484	3,595
Total unproved properties excluded from amortization	$102,338	$67,892

Property_Plant_And_Equipment_A

Property, Plant And Equipment (Average Sales Price and Production Costs Per Unit of Production) (Details) (USD $)	3 Months Ended						9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2013	Sep. 30, 2012
Average Sales Price and Production Costs Per Unit of Production [Line Items]	'	'	'	'	'	'	'	'
Impairment recorded (pre-tax) (in thousands)	$0	$0	$0	$78,054	$72,733	$0	$0	$150,787
Henry Hub natural gas price (per MMBtu)	'	'	'	'	'	'	'	'
Average Sales Price and Production Costs Per Unit of Production [Line Items]	'	'	'	'	'	'	'	'
Average price per Mcfe	3.61	3.44	2.95	2.83	3.15	3.73	'	'
West Texas Intermediate oil price (per Bbl)	'	'	'	'	'	'	'	'
Average Sales Price and Production Costs Per Unit of Production [Line Items]	'	'	'	'	'	'	'	'
Average price per Mcfe	91.69	88.13	89.17	91.48	92.17	94.65	'	'

LongTerm_Debt_Narrative_Detail

Long-Term Debt (Narrative) (Details) (USD $)

Sep. 30, 2013

Dec. 31, 2012

Oct. 18, 2013

Oct. 17, 2013

15-May-13

Sep. 30, 2013

Oct. 18, 2013

Oct. 17, 2013

Sep. 30, 2013

Jun. 07, 2013

Jun. 05, 2013

Sep. 30, 2013

Jun. 07, 2013

Sep. 30, 2013

Oct. 28, 2009

Sep. 30, 2013

Mar. 31, 2013

Sep. 30, 2013

Subsequent Event

Senior Secured Notes Due 2018

Gastar Exploration USA

Senior Secured Notes

Federal Funds Rate

Second Amended and Restated Revolving Credit Facility

Amended and Restated Revolving Credit Facility

Subsequent Event

Minimum

Maximum

Federal Funds Rate

Prime Rate

Eurodollar Rate

Minimum

Maximum

Prime Rate

LIBO Rate

Quarter ending September 30, 2013

Each quarter thereafter

Minimum

Maximum

Minimum

Maximum

Minimum

Maximum

Minimum

Maximum

Line of Credit Facility [Line Items]

Revolving credit facility borrowing base

$50,000,000

$160,000,000

$47,500,000

Interest rate description

'federal funds rate plus

'prime rate

'LIBO

Applicable interest margin (percentage)

500.00%

1.00%

2.00%

3.00%

1.00%

2.00%

2.50%

3.50%

Annual commitment fee (percentage)

0.50%

Percentage of stock foreign subsidiary pledged as collateral for credit facility (percentage)

65.00%

Line of credit facility covenant compliance Current Ratio

0.6

Line of credit facility covenant compliance indebtedness to EBITDA Ratio

4.25

Line of credit facility covenant compliance EBITDA to Interest Expense Ratio on a four quarter rolling basis

2.5

Borrowings outstanding

Borrowing availability

50,000,000

Increase in adjusted consolidated net tangibles assets

17.50%

Percentage of proved developed producing reserves hedged allowed under credit facility agreement (percentage)

100.00%

Aggregate principal amount

200,000,000

325,000,000

200,000,000

Preferred Stock, Aggregate Amount of Cash Dividends Permitted to be Paid

20,000,000

12,500,000

Interest rate

8.63%

Percentage of aggregate principal amount

101.00%

Long-term debt

194,830,000

98,000,000

194,800,000

Original issue discounts

$5,200,000

Fair_Value_Measurements_Narrat

Fair Value Measurements (Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended
Fair Value Measurements (Narrative) (Details) (USD $)	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Amount reclassifed from unproved to proved properties	$98,000	$8,000,000	$19,100,000
Level 1	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Fair value of long-term debt	$199,300,000	$199,300,000	'

Fair_Value_Measurements_Fair_V

Fair Value Measurements (Fair Value Measurements, Recurring and Nonrecurring) (Details) (Fair Value, Measurements, Recurring, USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Derivative Assets [Abstract]	'	'
Assets, Commodity derivative contracts	$9,658	$9,168
Liabilities:	'	'
Liabilities, Commodity derivative contracts	-794	-2,703
Total	30,239	15,366
Level 1	'	'
Derivative Assets [Abstract]	'	'
Assets, Commodity derivative contracts	0	0
Liabilities:	'	'
Liabilities, Commodity derivative contracts	0	0
Total	21,375	8,901
Level 2	'	'
Derivative Assets [Abstract]	'	'
Assets, Commodity derivative contracts	0	0
Liabilities:	'	'
Liabilities, Commodity derivative contracts	0	0
Total	0	0
Level 3	'	'
Derivative Assets [Abstract]	'	'
Assets, Commodity derivative contracts	9,658	9,168
Liabilities:	'	'
Liabilities, Commodity derivative contracts	-794	-2,703
Total	8,864	6,465
Cash and Cash Equivalents	'	'
Derivative Assets [Abstract]	'	'
Cash and cash equivalents	21,375	8,901
Cash and Cash Equivalents \| Level 1	'	'
Derivative Assets [Abstract]	'	'
Cash and cash equivalents	21,375	8,901
Cash and Cash Equivalents \| Level 2	'	'
Derivative Assets [Abstract]	'	'
Cash and cash equivalents	0	0
Cash and Cash Equivalents \| Level 3	'	'
Derivative Assets [Abstract]	'	'
Cash and cash equivalents	$0	$0

Fair_Value_Measurements_Net_Ch

Fair Value Measurements (Net Change in the Assets and Liabilities Measured at Fair Value on a Recurring Basis and Included in the Level 3 Fair Value Category) (Details) (Level 3, Commodity, Fair Value, Measurements, Recurring, USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Balance at beginning of period	$4,335		$15,460		$6,465		$15,873
Total gains (losses) (realized or unrealized):	'		'		'		'
included in earnings	-5,263		-2,045		-2,229		4,594
Purchases	9,470		0		9,470		0
Issuances	0		0		0		0
Settlements	322	[1]	-4,314	[1]	-4,842	[1]	-11,366	[1]
Transfers in and (out) of Level 3	0		0		0		0
Balance at end of period	8,864		9,101		8,864		9,101
The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or (losses) relating to assets still held at September 30, 2013 and 2012	'		'		-7,156		-4,123
Unrealized hedge gain (loss)	'		'		'		'
Total gains (losses) (realized or unrealized):	'		'		'		'
The amount of total gains (losses) for the period included in earnings attributable to the change in unrealized gains or (losses) relating to assets still held at September 30, 2013 and 2012	($5,004)		($5,403)		'		'

[1]	Included in total revenues on the statement of operations.

Derivative_Instruments_And_Hed2

Derivative Instruments And Hedging Activity (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'	'	'	'
Unrealized hedge loss	($5,004)	($5,403)	($7,156)	($4,123)

Derivative_Instruments_And_Hed3

Derivative Instruments And Hedging Activity (Schedule of Notional Amounts and Wieghted Average Underlying Hedge Prices of Outstanding Derivative Positions) (Details)	9 Months Ended
	Sep. 30, 2013
	MMBTU
Natural Gas \| 2013 \| Protective Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500	[1]
Total of Notional Volume (MMBtu's or Bbls)	152,500	[1]
Base Fixed Price (Price per MMbtu or Bbl)	4.05	[1]
Short Put (Price per MMBtu)	3.79	[1]
Natural Gas \| 2013 \| Costless collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500	[2]
Total of Notional Volume (MMBtu's or Bbls)	77,500	[2]
Floor (Long) (Price per MMBtu)	5	[2]
Ceiling (Short) (Price per MMBtu)	6.45	[2]
Natural Gas \| 2013 \| Call spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500
Total of Notional Volume (MMBtu's or Bbls)	230,000
Call (Long) (Price per MMBtu)	4.75
Ceiling (Short) (Price per MMBtu)	5.25
Natural Gas \| 2013 \| Basis HSC	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	4,000	[3]
Total of Notional Volume (MMBtu's or Bbls)	368,000	[3]
Base Fixed Price (Price per MMbtu or Bbl)	-0.11	[3]
Natural Gas \| 2014 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	11,136
Total of Notional Volume (MMBtu's or Bbls)	4,064,500
Base Fixed Price (Price per MMbtu or Bbl)	4.06
Natural Gas \| 2014 \| Short calls	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500
Total of Notional Volume (MMBtu's or Bbls)	912,500
Ceiling (Short) (Price per MMBtu)	4.59
Crude Oil \| 2014 \| Costless collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	200	[4]
Total of Notional Volume (MMBtu's or Bbls)	73,000
Floor (Long) (Price per MMBtu)	98
Ceiling (Short) (Price per MMBtu)	98
Fixed Price Swap 1 \| Natural Gas \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	5,000
Total of Notional Volume (MMBtu's or Bbls)	460,000
Base Fixed Price (Price per MMbtu or Bbl)	3.65
Fixed Price Swap 1 \| Crude Oil \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	250	[4]
Total of Notional Volume (MMBtu's or Bbls)	23,000
Base Fixed Price (Price per MMbtu or Bbl)	103.95
Fixed Price Swap 1 \| Natural Gas Liquids \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	150
Total of Notional Volume (MMBtu's or Bbls)	13,800
Base Fixed Price (Price per MMbtu or Bbl)	41.06
Fixed Price Swap 2 \| Natural Gas \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	1,500
Total of Notional Volume (MMBtu's or Bbls)	138,000
Base Fixed Price (Price per MMbtu or Bbl)	3.85
Fixed Price Swap 2 \| Crude Oil \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	850	[4]
Total of Notional Volume (MMBtu's or Bbls)	78,200
Base Fixed Price (Price per MMbtu or Bbl)	99.77
Fixed Price Swap 2 \| Natural Gas Liquids \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	350
Total of Notional Volume (MMBtu's or Bbls)	32,200
Base Fixed Price (Price per MMbtu or Bbl)	39.38
Fixed Price Swap 3 \| Natural Gas \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	1,500
Total of Notional Volume (MMBtu's or Bbls)	138,000
Base Fixed Price (Price per MMbtu or Bbl)	4
Fixed Price Swap 3 \| Crude Oil \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	400	[4]
Total of Notional Volume (MMBtu's or Bbls)	36,800
Base Fixed Price (Price per MMbtu or Bbl)	94.86
Fixed Price Swap 4 \| Natural Gas \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	3,000
Total of Notional Volume (MMBtu's or Bbls)	276,000
Base Fixed Price (Price per MMbtu or Bbl)	4.06
Fixed Price Swap 4 \| Crude Oil \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	611	[4]
Total of Notional Volume (MMBtu's or Bbls)	56,200
Base Fixed Price (Price per MMbtu or Bbl)	92.8
Put 1 \| Crude Oil \| 2013 \| Put	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	1,000	[4],[5]
Total of Notional Volume (MMBtu's or Bbls)	31,000	[5]
Floor (Long) (Price per MMBtu)	103	[5]
Put 2 \| Crude Oil \| 2014 \| Put	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	900	[4],[6]
Total of Notional Volume (MMBtu's or Bbls)	162,900	[6]
Floor (Long) (Price per MMBtu)	98
Put 3 \| Crude Oil \| 2014 \| Put	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	750	[4],[7]
Total of Notional Volume (MMBtu's or Bbls)	138,000	[7]
Floor (Long) (Price per MMBtu)	93	[7]
Fixed Price Swap 5 \| Natural Gas \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500
Total of Notional Volume (MMBtu's or Bbls)	230,000
Base Fixed Price (Price per MMbtu or Bbl)	4.05
Fixed Price Swap 5 \| Crude Oil \| 2014 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	300	[4],[6]
Total of Notional Volume (MMBtu's or Bbls)	54,300	[6]
Base Fixed Price (Price per MMbtu or Bbl)	98.05	[6]
Fixed Price Swap 6 \| Natural Gas \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	12,663
Total of Notional Volume (MMBtu's or Bbls)	1,165,000
Base Fixed Price (Price per MMbtu or Bbl)	3.87
Fixed Price Swap 6 \| Crude Oil \| 2014 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	550	[4],[6]
Total of Notional Volume (MMBtu's or Bbls)	99,550	[6]
Base Fixed Price (Price per MMbtu or Bbl)	95.15	[6]
Fixed Price Swap 7 \| Natural Gas \| 2013 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500	[2]
Total of Notional Volume (MMBtu's or Bbls)	77,500	[2]
Base Fixed Price (Price per MMbtu or Bbl)	4.05	[2]
Short Put (Price per MMBtu)	0	[2]
Fixed Price Swap 7 \| Crude Oil \| 2014 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	200	[4],[7]
Total of Notional Volume (MMBtu's or Bbls)	36,800	[7]
Base Fixed Price (Price per MMbtu or Bbl)	93	[7]
Producer Three Way Collar 2 \| Crude Oil \| 2015 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	345	[4]
Total of Notional Volume (MMBtu's or Bbls)	126,100
Floor (Long) (Price per MMBtu)	85
Short Put (Price per MMBtu)	65
Ceiling (Short) (Price per MMBtu)	97.8
Producer Three Way Collar 3 \| Crude Oil \| 2015 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	400	[4]
Total of Notional Volume (MMBtu's or Bbls)	146,000
Floor (Long) (Price per MMBtu)	85
Short Put (Price per MMBtu)	70
Ceiling (Short) (Price per MMBtu)	96.5
Producer Three Way Collar 4 \| Crude Oil \| 2015 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	150	[4],[8]
Total of Notional Volume (MMBtu's or Bbls)	27,150	[8]
Floor (Long) (Price per MMBtu)	85	[8]
Short Put (Price per MMBtu)	65	[8]
Ceiling (Short) (Price per MMBtu)	96.25	[8]
Producer Three Way Collar 5 \| Crude Oil \| 2015 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	50	[4],[9]
Total of Notional Volume (MMBtu's or Bbls)	9,200	[9]
Floor (Long) (Price per MMBtu)	85	[9]
Short Put (Price per MMBtu)	65	[9]
Ceiling (Short) (Price per MMBtu)	96.25	[9]
Producer Three Way Collar 6 \| Crude Oil \| 2016 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	275	[4]
Total of Notional Volume (MMBtu's or Bbls)	100,600
Floor (Long) (Price per MMBtu)	85
Short Put (Price per MMBtu)	65
Ceiling (Short) (Price per MMBtu)	95.1
Producer Three Way Collar 7 \| Crude Oil \| 2016 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	330	[4]
Total of Notional Volume (MMBtu's or Bbls)	120,780
Floor (Long) (Price per MMBtu)	80
Short Put (Price per MMBtu)	65
Ceiling (Short) (Price per MMBtu)	97.35
Put Spread 1 \| Crude Oil \| 2014 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	200	[10],[4]
Total of Notional Volume (MMBtu's or Bbls)	24,400	[10]
Floor (Long) (Price per MMBtu)	93	[10]
Short Put (Price per MMBtu)	73	[10]
Put Spread 2 \| Crude Oil \| 2015 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	250	[4]
Total of Notional Volume (MMBtu's or Bbls)	91,250
Floor (Long) (Price per MMBtu)	89
Short Put (Price per MMBtu)	69
Put Spread 3 \| Crude Oil \| 2015 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	700	[4],[8]
Total of Notional Volume (MMBtu's or Bbls)	126,700	[8]
Floor (Long) (Price per MMBtu)	90	[8]
Short Put (Price per MMBtu)	70	[8]
Put Spread 4 \| Crude Oil \| 2015 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	600	[4],[9]
Total of Notional Volume (MMBtu's or Bbls)	110,400	[9]
Floor (Long) (Price per MMBtu)	87	[9]
Short Put (Price per MMBtu)	67	[9]
Put Spread 5 \| Crude Oil \| 2016 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	550	[4]
Total of Notional Volume (MMBtu's or Bbls)	201,300
Floor (Long) (Price per MMBtu)	85
Short Put (Price per MMBtu)	65
Put Spread 6 \| Crude Oil \| 2016 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	300	[4]
Total of Notional Volume (MMBtu's or Bbls)	109,800
Floor (Long) (Price per MMBtu)	85.5
Short Put (Price per MMBtu)	65.5
Put Spread 7 \| Crude Oil \| 2017 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	500	[4]
Total of Notional Volume (MMBtu's or Bbls)	182,500
Floor (Long) (Price per MMBtu)	82
Short Put (Price per MMBtu)	62
Put Spread 8 \| Crude Oil \| 2018 \| Put Spread	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	425	[4]
Total of Notional Volume (MMBtu's or Bbls)	103,275
Floor (Long) (Price per MMBtu)	80
Short Put (Price per MMBtu)	60
Producer Three Way Collar 8 \| Crude Oil \| 2017 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	242	[4]
Total of Notional Volume (MMBtu's or Bbls)	88,150
Floor (Long) (Price per MMBtu)	80
Short Put (Price per MMBtu)	60
Ceiling (Short) (Price per MMBtu)	98.7
Producer Three Way Collar 9 \| Crude Oil \| 2017 \| Producer Three Way Collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	280	[4]
Total of Notional Volume (MMBtu's or Bbls)	102,200
Floor (Long) (Price per MMBtu)	80
Short Put (Price per MMBtu)	65
Ceiling (Short) (Price per MMBtu)	97.25
Fixed Price Swap 8 \| Natural Gas \| 2015 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	3,000
Total of Notional Volume (MMBtu's or Bbls)	1,095,000
Base Fixed Price (Price per MMbtu or Bbl)	4
Fixed Price Swap 8 \| Crude Oil \| 2014 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	350	[4],[7]
Total of Notional Volume (MMBtu's or Bbls)	64,400	[7]
Base Fixed Price (Price per MMbtu or Bbl)	91.55	[7]
Fixed Price Swap 9 \| Natural Gas \| 2015 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500
Total of Notional Volume (MMBtu's or Bbls)	912,500
Base Fixed Price (Price per MMbtu or Bbl)	4.06
Fixed Price Swap 9 \| Crude Oil \| 2014 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	500	[4]
Total of Notional Volume (MMBtu's or Bbls)	182,500
Base Fixed Price (Price per MMbtu or Bbl)	91.1
Fixed Price Swap 10 \| Natural Gas \| 2016 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,000
Total of Notional Volume (MMBtu's or Bbls)	732,000
Base Fixed Price (Price per MMbtu or Bbl)	4.11
Fixed Price Swap 10 \| Crude Oil \| 2014 \| Fixed price swap	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	270	[4]
Total of Notional Volume (MMBtu's or Bbls)	98,500
Base Fixed Price (Price per MMbtu or Bbl)	90.77
Costless Three Way Collar 1 [Member] \| Natural Gas \| 2013 \| Short calls	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	2,500	[1]
Total of Notional Volume (MMBtu's or Bbls)	152,500	[1]
Floor (Long) (Price per MMBtu)	0	[1]
Short Put (Price per MMBtu)	0	[1]
Ceiling (Short) (Price per MMBtu)	6.45	[1]
Costless Three Way Collar 2 [Member] \| Natural Gas \| 2014 \| Costless three way collar	'
Derivative [Line Items]	'
Average Daily Volume (MMBtus or Bbls)	10,500
Total of Notional Volume (MMBtu's or Bbls)	3,832,500
Floor (Long) (Price per MMBtu)	3.88
Short Put (Price per MMBtu)	3
Ceiling (Short) (Price per MMBtu)	4.53

[1]	For the period November to December 2013.
[2]	For the period July to October 2013.
[3]	East Houston-Katy - Houston Ship Channel
[4]	Crude volumes hedged include oil, condensate and certain components of our NGLs production.
[5]	For the period December 2013.
[6]	For the period January to June 2014.
[7]	For the period July to December 2014.
[8]	For the period January to June 2015.
[9]	For the period July to December 2015.
[10]	For the period September to December 2014.

Derivative_Instruments_And_Hed4

Derivative Instruments And Hedging Activity Schedule of Unamortized Put Premium Liabilities (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'	'
Current commodity derivative premium put payable	$1,819	$0
Long-term commodity derivative premium payable	7,651	0
Total unamortized put premium liabilities	$9,470	$0

Derivative_Instruments_And_Hed5

Derivative Instruments And Hedging Activity (Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location) (Details) (USD $)

9 Months Ended

3 Months Ended

9 Months Ended

In Thousands, unless otherwise specified

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Natural gas, condensate, oil and NGLs revenues

Unrealized hedge loss

Derivatives not designated as hedging instruments

Natural gas, condensate, oil and NGLs revenues

Unrealized hedge loss

Interest expense

Current assets

Other assets

Current liabilities

Long-term liabilities

Derivatives, Fair Value [Line Items]

Commodity derivative contracts, Assets

$2,259

$7,799

$7,399

$1,369

Commodity derivative contracts, Liabilities

-794

-1,399

-1,304

Total derivatives not designated as hedging instruments

8,864

6,465

Amount of Gain (Loss) Recognized in Income on Derivatives

($2,229)

$4,594

$4,927

$8,847

($7,156)

($4,123)

($5,263)

($2,045)

($259)

$3,404

($5,004)

($5,403)

($46)

($130)

Capital_Stock_Narrative_Detail

Capital Stock (Narrative) (Details) (USD $)

9 Months Ended

0 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Jun. 03, 2012

Jun. 02, 2012

Jun. 07, 2013

Sep. 30, 2013

Dec. 31, 2012

24-May-11

Oct. 25, 2013

Sep. 30, 2013

Jun. 07, 2013

Mar. 28, 2013

Sep. 30, 2013

Oct. 24, 2013

Nov. 04, 2013

Oct. 29, 2013

Nov. 01, 2013

Oct. 31, 2013

Oct. 25, 2013

Sep. 30, 2013

Chesapeake Energy Corporation

Gastar Exploration USA

Parent's 2006 Long-Term Stock Incentive Plan

Subsequent Event

At The Market Sales Agreement

Chesapeake Energy Corporation

Series A Preferred Stock

Series B Preferred Stock

At The Market Sales Agreement

Subsequent Event

Class of Stock [Line Items]

Common shares reserved for the exercise of stock options (shares)

909,100

11,000,000

6,000,000

1,931,793

Payment to settle legal claim

$10,800,000

$1,000,000

$10,800,000

Payments for repurchase of outstanding common shares

9,753,000

9,800,000

Repurchase of outstanding common shares (shares)

6,781,768

Common shares authorized for issuance (shares)

1,000

275,000,000

Common shares issued (shares)

61,134,950

66,432,609

750

Common stock par value per share

$0.00

Preferred shares authorized for issuance (shares)

10,000,000

40,000,000

Preferred stock par value per share

$0.01

Shares issued of Series A Preferred Stock

6,906

Proceeds from issuance of preferred stock, net of issuance costs

133,000

49,169,000

136,000

Preferred stock, shares sold (shares)

3,958,160

2,140,000

2,000,000

Liquidation Preference

$25

Number of additional shares under option to purchase shares

140,000

Net proceeds expected from offering of Series B Preferred Stock

50,100,000

Period after change in control to redeem preferred stock (days)

'90 days

Preferred stock, dividend rate, percentage (percentage)

8.63%

10.75%

Dividend on preferred stock

($2,100,000)

($6,400,000)

Preferred stock redemption price per share

$25

Option to convert shares of Series B Preferred Stock

11.5207

Dividend rate upon change in control (percentage)

12.75%

Capital_Stock_Schedule_of_Issu

Capital Stock (Schedule of Issuances and Forfeitures of Common Shares) (Details) (Unvested restricted shares)	3 Months Ended		9 Months Ended
	Sep. 30, 2013		Sep. 30, 2013
Unvested restricted shares	'		'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'		'
Restricted common shares granted (shares)	41,212		2,219,115
Restricted common shares vested (shares)	123,250		753,779
Common shares forfeited (shares)	32,751	[1]	222,144	[1]
Common shares canceled (shares)	466,535		512,862

[1]	Represents common shares forfeited in connection with the payment of estimated withholding taxes on restricted common shares that vested during the period.

Capital_Stock_Schedule_of_Pref

Capital Stock (Schedule of Preferred Stock Redemption Dates) (Details) (USD $)	Sep. 30, 2013
On or after June 23, 2013 and prior to June 23, 2014	'
Auction Market Preferred Securities, Stock Series [Line Items]	'
Redemption Price	$25.25
On or after June 23, 2014	'
Auction Market Preferred Securities, Stock Series [Line Items]	'
Redemption Price	$25

Equity_Compensation_PBUs_Narra

Equity Compensation - PBUs (Narrative) (Details) (PBUs, USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Compensation expense	$217	$722
2006 Long-Term Stock Incentive Plan	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Settlement of PBU's (percentage)	100.00%	100.00%
2006 Long-Term Stock Incentive Plan \| Minimum	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Settlement of PBU's (percentage)	0.00%	0.00%
2006 Long-Term Stock Incentive Plan \| Maximum	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Settlement of PBU's (percentage)	200.00%	200.00%

Equity_Compensation_PBUs_Summa

Equity Compensation - PBUs (Summary of PBUs) (Details) (PBUs, USD $)	9 Months Ended
	Sep. 30, 2013
PBUs	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]	'
Unvested PBUs at December 31, 2012	0
Granted	1,192,889
Vested	0
Forfeited	-127,155
Unvested PBUs at September 30, 2013	1,065,734
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]	'
Fair Value per Unit, Unvested PBUs at December 31, 2012	$0
Fair Value per Unit, Granted	$1.56
Fair Value per Unit, Vested	$0
Fair value per unit, Forfeited	$0
Fair Value per Unit, Unvested PBUs at September 30, 2013	$1.56

Interest_Expense_Schedule_of_C

Interest Expense (Schedule of Components of Interest Expense) (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Interest Expense [Abstract]	'		'		'		'
Cash and accrued	$4,376,000		$549,000		$8,238,000		$1,272,000
Amortization of deferred financing costs	340,000	[1],[2]	60,000	[1],[2]	1,790,000	[1],[2]	157,000	[1],[2]
Capitalized interest	-1,277,000		-579,000		-2,435,000		-1,343,000
Total interest expense	3,439,000		30,000		7,593,000		86,000
Deferred financing costs written off	'		'		1,200,000		'
Accretion of debt discount	$221,000		'		$330,000		'

[1]	The nine months ended SeptemberB 30, 2013 includes $1.2 million of deferred financing costs written off as a result of the new Revolving Credit Facility. See Note 4, bLong-Term Debt - Second Amended and Restated Revolving Credit Facility.b
[2]	The three and nine months ended SeptemberB 30, 2013 includes $221,000 and $330,000, respectively, of debt discount accretion related to the Notes.

Related_Party_Transactions_Nar

Related Party Transactions (Narrative) (Details) (USD $)	9 Months Ended		0 Months Ended	36 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Jun. 07, 2013	Dec. 31, 2007
	Sep. 30, 2013	Sep. 30, 2012	Chesapeake Energy Corporation	Chesapeake Energy Corporation
Related Party Transaction [Line Items]	'	'	'	'
Common shares aquired by Chesapeake Energy Corporation (shares)	'	'	'	6,781,768
Payment to settle legal claim	'	'	$10,800,000	'
Payments for repurchase of outstanding common shares	$9,753,000	$0	$9,800,000	'
Repurchase of outstanding common shares (shares)	'	'	6,781,768	'

Earnings_Per_Share_Schedule_of

Earnings Per Share (Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Net income (loss) attributable to Gastar Exploration Ltd.	($3,942)	($83,457)	$43,308	($163,802)
Weighted average common shares outstanding basic (shares)	57,359,357	63,601,645	61,159,117	63,494,224
Weighted average common shares outstanding diluted (shares)	57,359,357	63,601,645	63,971,038	63,494,224
Basic (dollars per share)	($0.07)	($1.31)	$0.71	($2.58)
Diluted (dollars per share)	($0.07)	($1.31)	$0.68	($2.58)
Common shares excluded from denominator as anti-dilutive (shares)	756,200	2,858,080	960,312	2,580,710
Unvested restricted shares	'	'	'	'
Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Incremental Common Shares Attributable to Share-based Payment Arrangements	0	0	2,565,888	0
Common shares excluded from denominator as anti-dilutive (shares)	0	1,878,355	41,212	1,654,439
Stock options	'	'	'	'
Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Common shares excluded from denominator as anti-dilutive (shares)	756,200	979,725	919,100	926,271
PBUs	'	'	'	'
Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Incremental Common Shares Attributable to Share-based Payment Arrangements	0	0	246,033	0

Commitments_And_Contingencies_

Commitments And Contingencies (Narrative) (Details) (USD $)	9 Months Ended		0 Months Ended			9 Months Ended		0 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Jun. 07, 2013	Jun. 07, 2013	Mar. 28, 2013	Sep. 30, 2013	Aug. 07, 2013	Dec. 17, 2010
			Chesapeake Energy Corporation	Chesapeake Energy Corporation	Chesapeake Energy Corporation	Chesapeake Exploration LLC and Chesapeake Energy Corporation vs Gastar Exploration Ltd, Gastar Exploration Texas LP, and Gastar Exploration Texas LLC	Gastar Exploration USA Inc v Williams Ohio Valley Midstream LLC	Gastar Exploration Ltd vs US Speciality Ins Co and Axis Ins Co
				Gastar Exploration USA	Gastar Exploration USA		Gastar Exploration USA
Loss Contingencies [Line Items]	'	'	'	'	'	'	'	'
Loss contingency, damages sought, value	'	'	'	'	'	$101,400,000	'	'
Amount paid by Chesapeake for the purchase of shares	'	'	'	'	'	76,000,000	'	'
Shares purchased by Chesapeake (shares)	'	'	'	'	'	5,430,329	'	'
Stock split, conversion ratio	'	'	'	'	'	5	'	'
Payment to settle legal claim	'	'	10,800,000	1,000,000	10,800,000	'	'	'
Payments for repurchase of outstanding common shares	9,753,000	0	9,800,000	9,800,000	'	'	'	'
Repurchase of outstanding common shares (shares)	'	'	6,781,768	'	6,781,768	'	'	'
Settlement aggregate amount	'	'	'	'	80,000,000	'	'	21,200,000
Payments to acquire oil and gas property	'	'	'	69,400,000	'	'	'	'
Counterclaim for damages	'	'	'	'	'	'	612,000	'
Combined coverage limits under directors and officers insurance	'	'	'	'	'	'	'	$20,000,000

Statement_Of_Cash_Flows_Supple2

Statement Of Cash Flows - Supplemental Information (Schedule of Supplemental Cash Paid and Non-cash Transactions) (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Supplemental Cash Flow Information [Abstract]	'	'
Cash paid for interest	$1,920	$1,280
Non-cash transactions:	'	'
Capital expenditures excluded from accounts payable and accrued drilling costs	-8,335	724
Capital expenditures excluded from prepaid expenses	0	99
Asset retirement obligation included in natural gas and oil properties	1,795	229
Asset retirement obligation assigned to operator	-362	-2,099
Application of advances to operators	14,443	5,848
Other	$61	$0