Antero Resources (AR) 10-Q6 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. 06, 2013
Document and Entity Information	'	'
Entity Registrant Name	'ANTERO RESOURCES Corp	'
Entity Central Index Key	'0001433270	'
Document Type	'10-Q	'
Document Period End Date	30-Sep-13	'
Amendment Flag	'false	'
Current Fiscal Year End Date	'--12-31	'
Entity Current Reporting Status	'Yes	'
Entity Filer Category	'Non-accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	262,049,659
Document Fiscal Period Focus	'Q3	'
Document Fiscal Year Focus	'2013	'

Condensed_Consolidated_Balance

Condensed 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	$11,584	$18,989
Accounts receivable	33,023	21,296
Notes receivable - current portion	3,111	4,555
Accrued revenue	86,122	46,669
Derivative instruments	204,857	160,579
Other	20,816	22,518
Total current assets	359,513	274,606
Oil and natural gas properties, at cost (successful efforts method):	'	'
Unproved properties	1,420,719	1,243,237
Proved properties	3,199,830	1,689,132
Gathering systems and facilities	455,818	168,930
Other property and equipment	12,741	9,517
Property and equipment, gross	5,089,108	3,110,816
Less accumulated depletion, depreciation, and amortization	-331,993	-173,343
Property and equipment, net	4,757,115	2,937,473
Derivative instruments	503,666	371,436
Notes receivable - long-term portion	'	2,667
Other assets, net	51,914	32,611
Total assets	5,672,208	3,618,793
Current liabilities:	'	'
Accounts payable	311,092	181,478
Accrued liabilities and other	103,359	61,161
Derivative instruments	309	'
Revenue distributions payable	68,926	46,037
Current portion of long-term debt	25,000	25,000
Deferred income tax liability	78,199	62,620
Total current liabilities	586,885	376,296
Long-term liabilities:	'	'
Long-term debt	2,970,455	1,444,058
Deferred income tax liability	202,708	91,692
Other long-term liabilities	34,333	33,010
Total liabilities	3,794,381	1,945,056
Equity:	'	'
Members' equity	1,460,947	1,460,947
Accumulated earnings	416,880	212,790
Total equity	1,877,827	1,673,737
Total liabilities and equity	$5,672,208	$3,618,793

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue:	'	'	'	'
Natural gas sales	$182,125	$66,796	$476,403	$156,618
Natural gas liquids sales	31,956	'	59,772	'
Oil sales	8,473	285	11,435	610
Commodity derivative fair value gains (losses)	161,968	-159,004	285,510	52,210
Loss on sale of assets	'	-115	'	'
Gain on sale of gathering system	'	'	'	291,190
Total revenue	384,522	-92,038	833,120	500,628
Operating expenses:	'	'	'	'
Lease operating	2,697	1,513	5,222	4,072
Gathering, compression, processing, and transportation	58,383	25,291	148,023	56,945
Production taxes	11,851	3,621	30,578	10,734
Exploration	5,372	3,156	17,034	7,912
Impairment of unproved properties	3,205	2,438	9,564	4,019
Depletion, depreciation, and amortization	65,697	26,858	158,650	65,289
Accretion of asset retirement obligations	266	25	797	71
General and administrative	14,443	11,938	40,727	31,584
Total operating expenses	161,914	74,840	410,595	180,626
Operating income (loss)	222,608	-166,878	422,525	320,002
Interest expense	-37,444	-22,453	-100,840	-71,046
Income (loss) from continuing operations before income taxes and discontinued operations	185,164	-189,331	321,685	248,956
Income tax (expense) benefit	-67,370	75,444	-120,695	-108,525
Income (loss) from continuing operations	117,794	-113,887	200,990	140,431
Discontinued operations:	'	'	'	'
Income (loss) from results of operations and sale of discontinued operations	3,100	-13,791	3,100	-418,465
Net income (loss) and comprehensive income (loss)attributable to Antero equity owners	$120,894	($127,678)	$204,090	($278,034)
Pro forma earnings (loss) per share - basic:	'	'	'	'
Continuing operations (in dollars per share)	$0.45	($0.44)	$0.77	$0.54
Discontinued operations (in dollars per share)	$0.01	($0.05)	$0.01	($1.60)
Net income (loss) (in dollars per share)	$0.46	($0.49)	$0.78	($1.06)
Pro forma earnings (loss) per share - diluted:	'	'	'	'
Continuing operations (in dollars per share)	$0.45	($0.44)	$0.77	$0.54
Discontinued operations (in dollars per share)	$0.01	($0.05)	$0.01	($1.60)
Net income (loss) (in dollars per share)	$0.46	($0.49)	$0.78	($1.06)
Pro forma weighted average number of shares outstanding:	'	'	'	'
Basic (in shares)	262,050	262,050	262,050	262,050
Diluted (in shares)	262,050	262,050	262,050	262,050

Condensed_Consolidated_Stateme1

Condensed 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)	$204,090	($278,034)
Adjustment to reconcile net income to net cash provided by operating activities:	'	'
Depletion, depreciation, amortization, and accretion	159,447	65,360
Impairment of unproved properties	9,564	4,019
Commodity derivative fair value gains	-285,510	-52,210
Cash receipts for settled derivatives	109,311	141,506
Gain on sale of assets	'	-291,190
Loss (gain) on sale of discontinued operations	-5,000	427,232
Deferred income tax expense	120,695	87,695
Depletion, depreciation, amortization, accretion, and impairment of unproved properties - discontinued operations	'	78,616
Commodity derivative fair value gains - discontinued operations	'	-46,358
Cash receipts for settled derivatives - discontinued operations	'	79,736
Deferred income tax expense - discontinued operations	1,900	4,085
Other	3,911	-4,567
Changes in current assets and liabilities:	'	'
Accounts receivable	-11,727	-16,811
Accrued revenue	-39,453	17,378
Other current assets	1,702	-3,112
Accounts payable	-4,602	-9,812
Accrued liabilities	44,720	7,281
Revenue distributions payable	22,889	-414
Other	'	15,000
Net cash provided by operating activities	331,937	225,400
Cash flows from investing activities:	'	'
Additions to proved properties	'	-4,451
Additions to unproved properties	-342,832	-428,574
Development costs	-1,267,086	-619,344
Additions to gathering systems and facilities	-240,119	-58,748
Additions to other property and equipment	-3,225	-2,786
Proceeds from asset sales	'	816,167
Changes in other assets	-11,622	2,556
Net cash used in investing activities	-1,864,884	-295,180
Cash flows from financing activities:	'	'
Issuance of senior notes	231,750	'
Borrowings on bank credit facility, net	1,295,500	82,000
Payments of deferred financing costs	-8,334	'
Other	6,626	992
Net cash provided by financing activities	1,525,542	82,992
Net increase (decrease) in cash and cash equivalents	-7,405	13,212
Cash and cash equivalents, beginning of period	18,989	3,343
Cash and cash equivalents, end of period	11,584	16,555
Supplemental disclosure of cash flow information:	'	'
Cash paid during the period for interest	-70,221	-61,930
Supplemental disclosure of noncash investing activities:	'	'
Increase in accounts payable for additions to properties, gathering systems, and facilities	$134,525	$73,430

Business_and_Organization

Business and Organization	9 Months Ended
Business and Organization	Sep. 30, 2013
Business and Organization	'
Business and Organization	'
	(1) Business and Organization

	Antero Resources LLC, a limited liability company, and its consolidated operating subsidiaries (collectively referred to as the Company, we, or our) are engaged in the exploration for and the production of natural gas, natural gas liquids (NGLs), and oil onshore in the United States in unconventional reservoirs, which can generally be characterized as fractured shales. Our properties are located in the Appalachian Basin in West Virginia, Ohio, and Pennsylvania. During 2012 we sold our Arkoma Basin and Piceance Basin properties. We have certain midstream gathering and pipeline operations. Our corporate headquarters are in Denver, Colorado.

	Our consolidated financial statements as of September 30, 2013 include the accounts of Antero Resources LLC and its directly and indirectly owned subsidiaries prior to the merger, as described below. The subsidiaries included in the consolidated financial statements are Antero Resources Corporation (ARC) (formerly Antero Resources Appalachian Corporation) and its wholly owned subsidiaries prior to the merger, Antero Resources Bluestone LLC and Antero Resources Finance Corporation (Antero Finance) (collectively referred to as the Antero Entities). Antero Resources LLC, the stand alone parent entity, had insignificant independent assets and no operations. In September 2013, we formed Antero Resources Midstream LLC (Antero Midstream). We intend to tranfer our midstream business to Antero Midstream.

	On October 16, 2013, in connection with a corporate reorganization that was completed immediately prior to the closing of ARC’s initial public offering, the members of Antero Resources LLC exchanged their membership interests in Antero Resources LLC for identical membership interests in Antero Resources Investment LLC (“Antero Investment”), which was a wholly owned subsidiary of Antero Resources LLC. Following the exchange of membership interests, pursuant to the merger agreement by and among Antero Resources LLC, Antero Investment and ARC, (a) Antero Resources LLC merged with and into ARC, with ARC surviving the merger, (b) all of the membership interests of Antero Resources LLC held by Antero Investment converted into all 224,375,000 shares of outstanding common stock of ARC, and (c) the membership interest in Antero Investment held by Antero Resources LLC was cancelled. On the same date, ARC completed a public offering of its common stock and issued 37,674,659 additional shares of its common stock to the public for estimated proceeds of approximately $1.58 billion, net of commissions and expenses of the offering. As a result of this corporate reorganization, we expect to recognize non-cash stock compensation expense in the fourth quarter of 2013 of approximately $297.0 million. Approximately $217.0 million of additional stock compensation will be recognized over the remaining service period of the underlying equity compensation awards.

	The current and historical consolidated financial statements of Antero Resources LLC presented herein are identical with respect to the underlying financial information of ARC, which subsequent to September 30, 2013, became the reporting company with the Securities and Exchange Commission as a result of the aforementioned merger and initial public offering. The accompanying Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) contain pro forma earnings per share information based upon the 262,049,659 shares outstanding upon the public offering.

Basis_of_Presentation_and_Sign

Basis of Presentation and Significant Accounting Policies	9 Months Ended
Basis of Presentation and Significant Accounting Policies	Sep. 30, 2013
Basis of Presentation and Significant Accounting Policies	'
Basis of Presentation and Significant Accounting Policies	'
	(2) Basis of Presentation and Significant Accounting Policies

	(a) *Basis of Presentation*

	These consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the SEC) applicable to interim financial information and should be read in the context of the December 31, 2012 consolidated financial statements and notes thereto for a more complete understanding of the Company’s operations, financial position, and accounting policies. The December 31, 2012 consolidated financial statements have been filed with the SEC in the Company’s Annual Report on Form 10-K for the year ended December 31, 2012 and the IPO Prospectus.

	The accompanying unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) for interim financial information, and, accordingly, do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. In the opinion of management, the accompanying unaudited consolidated financial statements include all adjustments (consisting of normal and recurring accruals) considered necessary to present fairly the Company’s financial position as of September 30, 2013, and the results of its operations for the three and nine months ended September 30, 2012 and 2013, and its cash flows for the nine months ended September 30, 2012 and 2013. We have no items of other comprehensive income or loss; therefore, our net income (loss) is identical to our comprehensive income (loss). All significant intercompany accounts and transactions have been eliminated. Operating results for the period ended September 30, 2013 are not necessarily indicative of the results that may be expected for the full year because of the impact of fluctuations in prices received for natural gas and oil, natural production declines, the uncertainty of exploration and development drilling results, and other factors.

	The Company’s exploration and production activities are accounted for under the successful efforts method.

	As of the date these financial statements were filed with the Securities and Exchange Commission, the Company completed its evaluation of potential subsequent events for disclosure and no items requiring disclosure were identified, except the public stock offering and a refinancing of the senior notes described in Note 11. See Note 1 for a description of the merger and public stock offering completed on October 16, 2013.

	(b) *Use of Estimates*

	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Changes in facts and circumstances or discovery of new information may result in revised estimates, and actual results could differ from those estimates.

	The Company’s financial statements are based on a number of significant judgments, assumptions, and estimates, including estimates of gas and oil reserve quantities, which are the basis for the calculation of depreciation, depletion, and amortization, present value of future reserves, and impairment of oil and gas properties. Reserve estimates are, by their nature, inherently imprecise.

	(c) *Risks and Uncertainties*

	Historically, the market for natural gas has experienced significant price fluctuations. Prices for natural gas, NGLs, and oil are volatile; price fluctuations can result from variations in weather, levels of production in a given region, availability of transportation capacity to other regions of the country, and various other factors. Increases or decreases in prices received could have a significant impact on the Company’s future results of operations.

	(d) *Cash and Cash Equivalents*

	The Company considers all liquid investments purchased with an initial maturity of three months or less to be cash equivalents. The carrying value of cash and cash equivalents approximates fair value due to the short-term nature of these investments.

	(e) *Derivative Financial Instruments*

	In order to manage its exposure to oil and gas price volatility, the Company enters into derivative transactions from time to time, which may include commodity swap agreements, collar agreements, and other similar agreements relating to oil and natural gas expected to be produced. From time to time, the Company may also enter into derivative contracts to mitigate the effects of interest rate fluctuations. To the extent legal right of offset with a counterparty exists, the Company reports derivative assets and liabilities on a net basis. The Company has exposure to credit risk to the extent the counterparty is unable to satisfy its settlement obligation. The fair value of the Company’s commodity derivative contracts of approximately $708 million at September 30, 2013 includes the following asset values by bank counterparty: Credit Suisse — $174 million; BNP Paribas — $156 million; Wells Fargo — $116 million; JP Morgan — $113 million; Barclays — $112 million; CitiBank - $23 million; Deutsche Bank — $11 million; Toronto Dominion Bank — $2 million; and Union Bank — $1 million. The credit ratings of certain of these banks have been downgraded because of the sovereign debt crisis in Europe. The estimated fair value of our commodity derivative assets has been risk adjusted using a discount rate based upon the respective published credit default swap rates (if available, or if not available, a discount rate based on the applicable Reuters bond rating) at September, 2013 for each of the European and North American banks. We believe that all of these institutions currently are acceptable credit risks.

	The Company records derivative instruments on the consolidated balance sheets as either an asset or liability measured at fair value and records changes in the fair value of derivatives in current earnings as they occur. Changes in the fair value of commodity derivatives are classified as revenues.

	(f) *Fair Value Measurements*

	Authoritative accounting guidance defines fair value, establishes a framework for measuring fair value, and requires disclosures about fair value measurements. This guidance also relates to all nonfinancial assets and liabilities that are not recognized or disclosed on a recurring basis (e.g., those measured at fair value in a business combination, the initial recognition of asset retirement obligations, and impairments of proved oil and gas properties, and other long-lived assets). The fair value is the price that the Company estimates would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. A fair value hierarchy is used to prioritize input to valuation techniques used to estimate fair value. An asset or liability subject to the fair value requirements is categorized within the hierarchy 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 in its entirety requires judgment and considers factors specific to the asset or liability. The highest priority (Level 1) is given to unadjusted quoted market prices in active markets for identical assets or liabilities, and the lowest priority (Level 3) is given to unobservable inputs. Level 2 inputs are data, other than quoted prices included within Level 1, that are observable for the asset or liability, either directly or indirectly. Instruments that are valued using Level 2 inputs include nonexchange traded derivatives, such as over-the-counter commodity price swaps, basis swaps, and interest rate swaps. Valuation models used to measure fair value of these instruments consider various Level 2 inputs including (i) quoted forward prices for commodities, (ii) time value, (iii) quoted forward interest rates, (iv) current market prices and contractual prices for the underlying instruments, (v) risk of nonperformance by the Company and the counterparty, and (vi) other relevant economic measures. To the extent a legal right of offset with a counterparty exists, the derivative assets and liabilities are reported on a net basis.

	(g) *Income Taxes*

	Prior to the merger described in Note 1, Antero Resources LLC and its subsidiaries filed separate federal and state income tax returns. Antero Resources LLC was a partnership for income tax purposes and therefore is not subject to federal or state income taxes. The tax on the income of Antero Resources LLC was borne by the individual members through the allocation of taxable income.

	Antero Resources Corporation and its subsidiaries recognize deferred tax assets and liabilities for temporary differences resulting from net operating loss carryforwards for income tax purposes and the differences between the financial statement and tax basis of assets and liabilities. The effect of changes in the tax laws or tax rates is recognized in income in the period such changes are enacted. Deferred tax assets are reduced by a valuation allowance, when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized.

	Unrecognized tax benefits represent potential future tax obligations for uncertain tax positions taken on previously filed tax returns that may not ultimately be sustained. The Company recognizes interest expense related to unrecognized tax benefits in interest expense and fines and penalties as income tax expense. The tax years 2009 through 2012 remain open to examination by the U.S. Internal Revenue Service. The Company files tax returns with various state taxing authorities which remain open to examination for tax years 2008 through 2012.

	(h) *Impairment of Unproved Properties*

	Unproved properties are assessed for impairment on a property-by-property basis, and any impairment in value is charged to expense. Impairment is assessed based on remaining lease terms, drilling results, reservoir performance, commodity price outlooks, and future plans to develop acreage.

	Impairment of unproved properties during the three months ended September 30, 2012 and 2013 was $2 million and $3 million, respectively. Impairment of unproved properties during the nine months ended September 30, 2012 and 2013 was $5 million and $10 million, respectively.

	(i) *Industry Segment and Geographic Information*

	We have evaluated how the Company is organized and managed and have identified one operating segment — the exploration and production of oil, natural gas, and natural gas liquids. We consider our gathering, processing, and marketing functions as ancillary to our oil and gas producing activities. All of our assets are located in the United States and all of our revenues are attributable to United States customers.

	(j) *Guarantees*

	In November 2009 and January 2010, an indirect wholly owned finance subsidiary of Antero Resources LLC, Antero Finance, issued $375 million and $150 million, respectively, of 9.375% senior notes due December 1, 2017. In August 2011, Antero Finance issued $400 million of 7.25% senior notes due August 1, 2019. In November 2012 and February 2013, Antero Finance issued $300 million and $225 million, respectively, of 6.00% senior notes due December 1, 2020. For purposes of this footnote, we collectively refer to the 2017 senior notes, the 2019 senior notes and the 2020 senior notes as the “senior notes.”

	Antero Resources LLC, as the parent company (for purposes of this footnote only, the Parent Company), has no independent assets or operations. Antero Finance is a 100% indirectly owned finance subsidiary of Parent Company. The senior notes are each guaranteed on a senior unsecured basis by Parent Company and all of Parent Company’s wholly owned subsidiaries (other than Antero Finance) and certain of its future restricted subsidiaries. The guarantees are full and unconditional and joint and several. The guarantor subsidiaries may be released from those guarantees upon the occurrence of certain events, including (i) the designation of that subsidiary guarantor as an unrestricted subsidiary; (ii) the release or discharge of any guarantee or indebtedness that resulted in the creation of the guarantee of the senior notes by such subsidiary guarantor; or (iii) the sale or other disposition, including the sale of substantially all of the assets, of that subsidiary guarantor. There are no significant restrictions on Antero Finance’s ability to obtain funds from the Parent Company or the subsidiary guarantors by dividend or loan, except those imposed by applicable law. However, the indentures governing the senior notes and the Credit Facility agreement contain significant restrictions on the ability of Antero Finance or the subsidiary guarantors to make distributions to the Parent Company. Finally, the Parent Company’s wholly owned subsidiaries do not have restricted assets that exceed 25% of net assets as of the most recent fiscal year end that may not be transferred to the Parent Company in the form of loans, advances or cash dividends by the subsidiaries without the consent of a third party.

Sale_of_Piceance_and_Arkoma_Pr

Sale of Piceance and Arkoma Properties - Discontinued Operations (Piceance Basin and Arkoma Basin)	9 Months Ended
	Sep. 30, 2013
Piceance Basin and Arkoma Basin	'
Sale of Assets	'
Sale of Piceance and Arkoma Properties - Discontinued Operations	'
	(3) Sale of Piceance and Arkoma Properties — Discontinued Operations

	On December 21, 2012, the Company completed the sale of its Piceance Basin assets. The $316 million of net proceeds from the sale represented the purchase price of $325 million, adjusted for expenses of the sale and estimated income, expenses, and capital costs related to the Piceance Basin properties from the October 1, 2012 effective date of the sale through December 21, 2012. The agreement to sell the properties is subject to post-closing adjustments for up to a one year period. The Company believes that post-closing adjustments, if any, will not have a material effect on the financial statements. The Company recognized a loss of $364 million on the sale of the Piceance Basin assets in the fourth quarter of 2012. The purchaser also assumed all of the Company’s Rocky Mountain firm transportation obligations, which totaled approximately $100 million. In connection with the sale of the Piceance Basin assets, the Company also liquidated its hedge positions related to the Piceance Basin and realized additional proceeds of approximately $100 million.

	On June 29, 2012, the Company completed its sale of its Arkoma Basin assets and associated the commodity hedges. Proceeds from the sale of $427 million represent the purchase price of $445 million adjusted for expenses of the sale and estimated income, expenses, and capital costs from the effective date of the sale through the closing date of June 29, 2012. The agreement to sell the properties is subject to post-closing adjustments for up to a two year period. The Company believes that post-closing adjustments, if any, will not have a material effect on the financial statements. The Company recognized a loss of $427 million on the sale of the Arkoma Basin assets in the second quarter of 2012.

	During the three and nine months ended September 30, 2013, the Company recorded pre-tax income of $5 million, or $3,100 net of taxes, related to operations that were discontinued in 2012 for sales tax refunds received and reductions in estimated expenses related to discontinued operations. Results of operations for the three months and nine months ended September 30, 2012 for the Piceance Basin and Arkoma Basin assets are shown as discontinued operations on the accompanying Consolidated Statement of Operations and Comprehensive Income (Loss) and are comprised of the following (in thousands):

		Three months			Nine months
		Ended			ended
		September 30, 2012			September 30, 2012
	Sales of oil, natural gas, and natural gas liquids	$	22,690		105,096
	Commodity derivative fair value gains (losses)	(18,880		)	46,358
	Total revenues	3,810			151,454
	Lease operating expenses	2,430			16,395
	Gathering, compression, and transportation	7,685			38,210
	Production taxes	1,776			4,874
	Exploration expenses	95			507
	Impairment of unproved properties	(31		)	962
	Depletion, depreciation, and amortization	14,197			77,344
	Accretion of asset retirement obligations	91			310
	Loss on sale of discontinued operations	—			427,232
	Total expenses	26,243			565,834
	Loss from discontinued operations before income taxes	(22,433		)	(414,380	)
	Income tax (expense) benefit	8,642			(4,085	)
	Net loss from discontinued operations attributable to Antero equity owners	$	(13,791	)	(418,465	)

Longterm_Debt

Long-term Debt	9 Months Ended
	Sep. 30, 2013
Long-term Debt	'
Long-term Debt	'
	(4) Long-term Debt

	Long-term debt consists of the following at December 31, 2012 and September 30, 2013 (in thousands):

		December 31,		September 30,
		2012		2013
	Bank credit facility (a)	$	217,000	1,512,500
	9.375% senior notes due 2017 (b)	525,000		525,000
	7.25% senior notes due 2019 (c)	400,000		400,000
	6.00% senior notes due 2020 (d)	300,000		525,000
	9.00% senior note (d)	25,000		25,000
	Net premium	2,058		7,955
		1,469,058		2,995,455
	Less amounts due within one year	25,000		25,000
	Total	$	1,444,058	2,970,455

	(a) *Bank Credit Facility*

	The Company has a senior secured revolving bank credit facility (the Credit Facility) with a consortium of bank lenders. The maximum amount of the Credit Facility is $2.5 billion. Borrowings under the Credit Facility are subject to borrowing base limitations based on the collateral value of the Company’s proved properties and commodity hedge positions and are subject to regular semiannual redeterminations. At September 30, 2013, the borrowing base is $2.0 billion and lender commitments were $1.75 billion. Lender commitments can be increased to the full amount of the borrowing base upon approval of the lenders. The next redetermination of the borrowing base is scheduled to occur in April 2014. The maturity date of the Credit Facility is May 12, 2016. Subsequent to September 30, 2013, lender commitments under the Credit Facility were reduced to $1.5 billion.

	The Credit Facility is secured by mortgages on substantially all of the Company’s properties and guarantees from the Company’s operating subsidiaries. The Credit Facility contains certain covenants, including restrictions on indebtedness and dividends, and requirements with respect to working capital and interest coverage ratios. Interest is payable at a variable rate based on LIBOR or the prime rate based on the Company’s election at the time of borrowing. The Company was in compliance with all of the financial covenants under the Credit Facility as of December 31, 2012 and September 30, 2013.

	As of September 30, 2013, the Company had an outstanding balance under the Credit Facility of $1.5 billion, with a weighted average interest rate of 2.3%, and outstanding letters of credit of approximately $32 million. As of December 31, 2012, the Company had an outstanding balance under the Credit Facility of $217 million, with a weighted average interest rate of 1.91%, and outstanding letters of credit of approximately $43 million. Commitment fees on the unused portion of the Credit Facility are due quarterly at rates ranging from 0.375% to 0.50% of the unused facility based on utilization.

	(b) *9.375% Senior Notes Due 2017*

	On November 17, 2009 Antero Finance issued $375 million of 9.375% senior notes due December 1, 2017 at a discount of $2.6 million. In January 2010, the Company issued an additional $150 million of the same series of 9.375% senior notes at a premium of $6.0 million. The notes are unsecured and effectively subordinated to the Company’s Credit Facility to the extent of the value of the collateral securing the Credit Facility. The notes are guaranteed on a full and unconditional basis and joint and severally by the Company, all of its wholly owned subsidiaries (other than Antero Finance), and certain of its future restricted subsidiaries. Interest on the notes is payable on June 1 and December 1 of each year. Antero Finance may redeem all or part of the notes at any time on or after December 1, 2013 at redemption prices ranging from 104.688% on or after December 1, 2013 to 100% on or after December 1, 2015. At any time prior to December 1, 2013, Antero Finance may also redeem the notes, in whole or in part, at a price equal to 100% of the principal amount of the notes plus a “make-whole” premium. If the Company undergoes a change of control, Antero Finance may be required to offer to purchase notes from the holders.

	The 9.375% senior notes due 2017 will be redeemed with the proceeds of the issuance of the 5.375% notes issued subsequent to September 30, 2013. See Note 11.

	(c) *7.25% Senior Notes Due 2019*

	On August 1, 2011, Antero Finance issued $400 million of 7.25% senior notes due August 1, 2019 at par. The notes are unsecured and effectively subordinated to the Company’s Credit Facility to the extent of the value of the collateral securing the Credit Facility. The notes rank pari passu to the existing 9.375% senior notes. The notes are guaranteed on a senior unsecured basis by the Company, all of its wholly owned subsidiaries (other than Antero Finance), and certain of its future restricted subsidiaries. Interest on the notes is payable on August 1 and February 1 of each year. Antero Finance may redeem all or part of the notes at any time on or after August 1, 2014 at redemption prices ranging from 105.438% on or after August 1, 2014 to 100% on or after August 1, 2017. In addition, on or before August 1, 2014, Antero Finance may redeem up to 35% of the aggregate principal amount of the notes with the net cash proceeds of certain equity offerings, if certain conditions are met, at a redemption price of 107.25% of the principal amount of the notes, plus accrued interest. At any time prior to August 1, 2014, Antero Finance may redeem the notes, in whole or in part, at a price equal to 100% of the principal amount of the notes plus a “make-whole” premium and accrued interest. If the Company undergoes a change of control, the note holders will have the right to require Antero Finance to repurchase all or a portion of the notes at a price equal to 101% of the principal amount of the notes, plus accrued interest.

	The Company will redeem 35% of the 7.25% senior notes due 2019 from the proceeds of the initial public offering. See Note 11.

	(d) *6.00% Senior Notes Due 2020*

	On November 19, 2012, Antero Finance issued $300 million of 6.00% senior notes due December 1, 2020 at par. In a subsequent transaction, on February 4, 2013 Antero Finance issued an additional $225 million of the 6.00% notes at 103% of par. The notes are unsecured and effectively subordinated to the Company’s Credit Facility to the extent of the value of the collateral securing the Credit Facility. The notes rank pari passu to the existing 9.375% and 7.25% senior notes. The notes are guaranteed on a senior unsecured basis by the Company, all of its wholly owned subsidiaries (other than Antero Finance), and certain of its future restricted subsidiaries. Interest on the notes is payable on June 1 and December 1 of each year. Antero Finance may redeem all or part of the notes at any time on or after December 1, 2015 at redemption prices ranging from 104.50% on or after December 1, 2015 to 100% on or after December 1, 2018. In addition, on or before December 1, 2015, Antero Finance may redeem up to 35% of the aggregate principal amount of the notes with the net cash proceeds of certain equity offerings, if certain conditions are met, at a redemption price of 106.00% of the principal amount of the notes, plus accrued interest. At any time prior to December 1, 2015, Antero Finance may redeem the notes, in whole or in part, at a price equal to 100% of the principal amount of the notes plus a “make-whole” premium and accrued interest. If a change of control (as defined in the bond indenture) occurs at any time prior to January 1, 2014, Antero Finance may, at its option, redeem all, but not less than all, of the notes at a redemption price equal to 110% of the principal amount of the notes, plus accrued interest. If the Company undergoes a change of control, the note holders will have the right to require Antero Finance to repurchase all or a portion of the notes at a price equal to 101% of the principal amount of the notes, plus accrued interest.

	(e) *9.00% Senior Note*

	The Company assumed a $25 million unsecured note payable in a business acquisition consummated on December 1, 2010. The note bears interest at 9% and is due December 1, 2013.

	(f) *Treasury Management Facility*

	The Company has a stand-alone revolving note with a lender under the Credit Facility which provides for up to $25 million of cash management obligations in order to facilitate the Company’s daily treasury management. Borrowings under the revolving note are secured by the collateral for the revolving credit facility. Borrowings under the facility bear interest at the lender’s prime rate plus 1.0%. The note matures on June 1, 2014. At December 31, 2012 and September 30, 2013, there were no outstanding borrowings under this facility.

Ownership_Structure

Ownership Structure	9 Months Ended
	Sep. 30, 2013
Ownership Structure	'
Ownership Structure	'
	(5) Ownership Structure

	At December 31, 2012 and September 30, 2013, the outstanding units in Antero Resources LLC are summarized as follows:

		Units
		Authorized
		and issued
	Class I units	107,281,058
	Class A and B units	40,007,463
	Class A and B profits units	19,726,873
		167,015,394

	None of the three classes of outstanding units are entitled to current cash distributions or are convertible into indebtedness. The Company has no obligation to repurchase these units at the election of the unitholders.

	In the event of a distribution from Antero Resources LLC, amounts available for distribution are distributed according to a formula set forth in the Company’s limited liability company agreement that takes into account the relative priority of the various classes of units outstanding. In the event of a distribution due to the disposition of an individual Antero Entity, a portion of the proceeds is allocated to the employees of the Company based on a requisite return financial threshold. In general, distributions are made first to holders of the Class I units until they have received their investment amount and an 8% special allocation and then, as a group, to the holders of all classes of units together. The Class I units participate on a pro rata basis with the other classes of units in funds available for distributions in excess of the Class I unit investment and special allocation amounts.

	At December 31, 2012 and September 30, 2013, the Class I units had an aggregate liquidation priority, including the special allocation of 8% per annum, of $2.191 billion and $2.325 billion, respectively.

Financial_Instruments

Financial Instruments	9 Months Ended
Financial Instruments	Sep. 30, 2013
Financial Instruments	'
Financial Instruments	'
	(6) Financial Instruments

	The carrying values of trade receivables, trade payables, and the Credit Facility at December 31, 2012 and September 30, 2013 approximated market value. The carrying value of the Credit Facility at December 31, 2012 and September 30, 2013 approximated fair value because the variable interest rates are reflective of current market conditions. Based on Level 2 market data, the fair value of the Company’s senior notes was approximately $1.3 billion and $1.5 billion at December 31, 2012 and September 30, 2013, respectively.

Asset_Retirement_Obligations

Asset Retirement Obligations	9 Months Ended
	Sep. 30, 2013
Asset Retirement Obligations	'
Asset Retirement Obligations	'
	(7) Asset Retirement Obligations

	The following is a reconciliation of the Company’s asset retirement obligations, included in other long-term liabilities on the condensed consolidated balance sheets, for the nine months ended September 30, 2013 (in thousands):

	Asset retirement obligations — beginning of period	$	10,552
	Obligations incurred	69
	Accretion expense	797
	Asset retirement obligations — end of period	$	11,418

Derivative_Instruments_and_Ris

Derivative Instruments and Risk Management Activities	9 Months Ended
Derivative Instruments and Risk Management Activities	Sep. 30, 2013
Derivative Instruments and Risk Management Activities	'
Derivative Instruments and Risk Management Activities	'
	(8) Derivative Instruments and Risk Management Activities

	(a) *Commodity Derivatives*

	The Company periodically enters into natural gas and oil derivative contracts with counterparties to hedge the price risk associated with a portion of its production. These derivatives are not held for trading purposes. To the extent that changes occur in the market prices of natural gas and oil, the Company is exposed to market risk on these open contracts. This market risk exposure is generally offset by the change in market prices of natural gas and oil recognized upon the ultimate sale of the natural gas and oil produced.

	For the nine months ended September 30, 2012 and 2013, the Company was party to oil and natural gas fixed price swaps. When actual commodity prices exceed the fixed price provided by the swap contracts, the Company pays the excess to the counterparty, and when actual commodity prices are below the contractually provided fixed price, the Company receives the difference from the counterparty. The Company’s natural gas and oil swaps have not been designated as hedges for accounting purposes; therefore, all gains and losses were recognized in income currently.

	The Company has no collateral from any counterparties. All but one of the Company’s commodity derivative positions are with institutions that are lenders under our Credit Facility and are secured by the collateral pledged on the Credit Facility and cross default provisions between the Credit Facility and the derivative instruments. At September 30, 2013, there were no past due receivables from or payables to any of our counterparties.

	As of September 30, 2013, the Company’s positions in fixed price natural gas and oil swaps from October 1, 2013 through December 31, 2019 are summarized in the following table:

			MMbtu/day		Bbls/day		Price
	Three Months ending December 31, 2013:
	CGTAP-TCO		260,000				$	4.56
	Dominion South		190,844				4.89
	NYMEX-WTI		—		4,300		103.97
	2013 Total		450,844		4,300
	Year ending December 31, 2014:
	CGLA		10,000				$	3.87
	CGTAP-TCO		210,000				5.11
	Dominion South		160,000				5.15
	NYMEX		120,000				4
	NYMEX-WTI		—		3,000		96.53
	2014 Total		500,000		3,000
	Year ending December 31, 2015:
	CGLA		40,000				$	4
	CGTAP-TCO		130,000				4.93
	Dominion South		230,000				5.6
	NYMEX		80,000				4.1
	2015 Total		480,000
	Year ending December 31, 2016:
	CGLA		170,000				$	4.09
	CGTAP-TCO		80,000				4.67
	Dominion South		272,500				5.35
	NYMEX		60,000				4.25
	2016 Total		582,500
	Year ending December 31, 2017:
	CGLA		420,000				$	4.27
	NYMEX		220,000				4.44
	CCG		70,000				4.57
	CGTAP-TCO		20,000				4.02
	2017 Total		730,000
	Year ending December 31, 2018:
	NYMEX		530,000				$	4.73
	Year ending December 31, 2019:
	NYMEX		87,500				$	4.75

	(b) *Summary*

	The following is a summary of the fair values of our derivative instruments, which are not designated as hedges for accounting purposes and where such values are recorded in the consolidated balance sheets as of December 31, 2012 and September 30, 2013 (in thousands):

			December 31, 2012					September 30, 2013
			Balance					Balance
			sheet					sheet
			location		Fair value			location		Fair value
	Asset derivatives not designated as hedges for accounting purposes:
	Commodity contracts		Current assets		$	160,579		Current assets		$	204,857
	Commodity contracts		Long-term assets		371,436			Long-term assets		503,666
	Total asset derivatives				532,015					708,523
	Liability derivatives not designated as hedges for accounting purposes:
	Commodity contracts		Current liabilities		—			Current liabilities		309
	Net asset fair value of derivatives				$	532,015				$	708,214

The following is a summary of realized and unrealized gains (losses) on derivative instruments and where such values are recorded in the consolidated statements of operations for the three months ended and nine months ended September 30, 2012 and 2013 (in thousands):

		Statement of		Three months ended					Nine months ended
		operations		September 30,					September 30,
		location		2012			2013		2012		2013
Commodity derivative fair value gains (losses)		Revenue		$	(159,004	)	161,968		52,210		285,510
Commodity derivative fair value gains (losses)		Discontinued operations		(18,880		)	—		46,358		—
Total gains (losses) on commodity contracts				$	(177,884	)	161,968		98,568		285,510

The following table summarizes the valuation of investments and financial instruments by the fair value hierarchy described in note 1 at September 30, 2013 (in thousands):

		Fair value measurements using
		Quoted
		prices
		in active			Significant
		markets for			other		Significant
		identical			observable		unobservable
		assets			inputs		inputs
Description		(Level 1)			(Level 2)		(Level 3)		Total
Net derivatives asset:
Fixed price commodity swaps		$	—		708,214		—		708,214


The following tables present the gross amounts of recognized derivative assets and liabilities, the amounts offset under netting arrangements with counterparties, and the resulting net amounts presented in the condensed consolidated balance sheets for the periods presented, all at fair value (in thousands):

		December 31, 2012							September 30, 2013
													Net amounts
							Net amounts						of assets
		Gross amounts			Gross amounts		of assets		Gross amounts		Gross amounts		(liabilities)
		of recognized			offset on		on balance		of recognized		offset on		on balance
		assets			balance sheet		sheet		assets		balance sheet		sheet
Commodity derivative assets		$	597,359		(65,344	)	532,015		715,960		(7,437	)	708,523
Commodity derivative liabilities		—			—		—		—		(309	)	(309	)

Sale_of_Appalachian_Gathering_

Sale of Appalachian Gathering Assets (Appalachian Gathering Assets)	9 Months Ended
	Sep. 30, 2013
Appalachian Gathering Assets	'
Sale of Assets	'
Sale of Appalachian Gathering Assets	'
	(9) Sale of Appalachian Gathering Assets

	On March 26, 2012, the Company closed the sale of a portion of its Marcellus Shale gathering system assets along with exclusive rights to gather the Company’s gas for a 20-year period within an area of dedication (AOD) to a joint venture owned by Crestwood Midstream Partners and Crestwood Holdings Partners LLC (together Crestwood) for $375 million (subject to customary purchase price adjustments). The sale included approximately 25 miles of low pressure pipeline systems and gathering rights on 104,000 net acres held by the Company within a 250,000 acre AOD and had an effective date of January 1, 2012. Other third-party producers will also have access to the Crestwood system. During the first seven years of the contract, the Company is committed to deliver minimum volumes into the gathering systems, with certain carryback and carryforward adjustments for overages or deficiencies. The Company can earn up to an additional $40 million of sale proceeds over a period of three years from the date of the sale if it meets certain volume thresholds. Crestwood is obligated to incur all future capital costs to build out the gathering systems and compression facilities within the AOD to connect the Company’s wells as it executes its drilling program and has assumed the various risks and rewards of the system build-out and operations. Because the Company has not retained the substantial risks and rewards of ownership associated with the gathering rights and systems transferred to Crestwood, a gain of approximately $291 million on the sale of the gathering system and rights was recognized during the first quarter of 2012.

Contingencies

Contingencies	9 Months Ended
Contingencies	Sep. 30, 2013
Contingencies	'
Contingencies	'
	(10) Contingencies

	The Company is party to various legal proceedings and claims in the ordinary course of its business. The Company believes certain of these matters will be covered by insurance and that the outcome of other matters will not have a material adverse effect on its consolidated financial position, results of operations, or liquidity.

Subsequent_Events

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2013
Subsequent Events	'
Subsequent Events	'
	(11) Subsequent Events

	Initial *Public Offering*

	On October 16, 2013, we completed our initial public offering of 41,083,750 shares of our common stock, including the exercise in full by the underwriters of their options to purchase an additional 3,409,091 shares of common stock from the selling stockholder and an additional 1,949,659 shares of common stock from us. Net proceeds received by us from the sale of 37,674,659 shares of common stock were approximately $1.58 billion, after deducting underwriting discounts. The proceeds from the offering were immediately used to paydown our Credit Facility, and ultimately will be used to redeem a portion of our outstanding senior notes and fund our development and production efforts. Antero Resources Corporation’s stock is traded on the New York Stock Exchange under the symbol “AR”.

	Issuance of 5.375% Senior Notes

	On November 5, 2013, Antero Finance issued $1 billion of 5.375% senior notes at par due November 1, 2021. Proceeds from the notes will be used to (i) finance the redemption of our 9.375% notes due 2017 and the repayment of the 9.0% senior note due December 1, 2013, (ii) repay the outstanding borrowings under the Credit Facility and (iii) fund our drilling and development program. The notes are unsecured and effectively subordinated to the Company’s Credit Facility to the extent of the value of the collateral securing the Credit Facility. The notes rank pari passu to the existing 7.25% and 6.00% senior notes. The notes are guaranteed on a senior unsecured basis by ARC and all of its wholly owned subsidiaries (other than Antero Finance), and certain of its future restricted subsidiaries. Interest on the notes is payable on May 1 and November 1 of each year. Antero Finance may redeem all or part of the notes at any time on or after November 1, 2016 at redemption prices ranging from 104.031% on or after November 1, 2016 to 100% on or after November 1, 2019. In addition, on or before November 1, 2016, Antero Finance may redeem up to 35% of the aggregate principal amount of the notes with the net cash proceeds of certain equity offerings, if certain conditions are met, at a redemption price of 105.375% of the principal amount of the notes, plus accrued interest. At any time prior to November 1, 2016, Antero Finance may redeem the notes, in whole or in part, at a price equal to 100% of the principal amount of the notes plus a “make-whole” premium and accrued interest. If a change of control (as defined in the bond indenture) occurs at any time prior to May 1, 2015, Antero Finance may, at its option, redeem all, but not less than all, of the notes at a redemption price equal to 110% of the principal amount of the notes, plus accrued interest. If ARC undergoes a change of control and there is a subsequent decline in ratings, the note holders will have the right to require Antero Finance to repurchase all or a portion of the notes at a price equal to 101% of the principal amount of the notes, plus accrued interest.

Basis_of_Presentation_and_Sign1

Basis of Presentation and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2013
Basis of Presentation and Significant Accounting Policies	'
Basis of Presentation	'
	(a) *Basis of Presentation*

	These consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the SEC) applicable to interim financial information and should be read in the context of the December 31, 2012 consolidated financial statements and notes thereto for a more complete understanding of the Company’s operations, financial position, and accounting policies. The December 31, 2012 consolidated financial statements have been filed with the SEC in the Company’s Annual Report on Form 10-K for the year ended December 31, 2012 and the IPO Prospectus.

	The accompanying unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) for interim financial information, and, accordingly, do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. In the opinion of management, the accompanying unaudited consolidated financial statements include all adjustments (consisting of normal and recurring accruals) considered necessary to present fairly the Company’s financial position as of September 30, 2013, and the results of its operations for the three and nine months ended September 30, 2012 and 2013, and its cash flows for the nine months ended September 30, 2012 and 2013. We have no items of other comprehensive income or loss; therefore, our net income (loss) is identical to our comprehensive income (loss). All significant intercompany accounts and transactions have been eliminated. Operating results for the period ended September 30, 2013 are not necessarily indicative of the results that may be expected for the full year because of the impact of fluctuations in prices received for natural gas and oil, natural production declines, the uncertainty of exploration and development drilling results, and other factors.

	The Company’s exploration and production activities are accounted for under the successful efforts method.

	As of the date these financial statements were filed with the Securities and Exchange Commission, the Company completed its evaluation of potential subsequent events for disclosure and no items requiring disclosure were identified, except the public stock offering and a refinancing of the senior notes described in Note 11. See Note 1 for a description of the merger and public stock offering completed on October 16, 2013.
Use of Estimates	'
	(b) *Use of Estimates*

	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Changes in facts and circumstances or discovery of new information may result in revised estimates, and actual results could differ from those estimates.

	The Company’s financial statements are based on a number of significant judgments, assumptions, and estimates, including estimates of gas and oil reserve quantities, which are the basis for the calculation of depreciation, depletion, and amortization, present value of future reserves, and impairment of oil and gas properties. Reserve estimates are, by their nature, inherently imprecise.
Risks and Uncertainties	'
	(c) *Risks and Uncertainties*

	Historically, the market for natural gas has experienced significant price fluctuations. Prices for natural gas, NGLs, and oil are volatile; price fluctuations can result from variations in weather, levels of production in a given region, availability of transportation capacity to other regions of the country, and various other factors. Increases or decreases in prices received could have a significant impact on the Company’s future results of operations.
Cash and Cash Equivalents	'
	(d) *Cash and Cash Equivalents*

	The Company considers all liquid investments purchased with an initial maturity of three months or less to be cash equivalents. The carrying value of cash and cash equivalents approximates fair value due to the short-term nature of these investments.
Derivative Financial Instruments	'
	(e) *Derivative Financial Instruments*

	In order to manage its exposure to oil and gas price volatility, the Company enters into derivative transactions from time to time, which may include commodity swap agreements, collar agreements, and other similar agreements relating to oil and natural gas expected to be produced. From time to time, the Company may also enter into derivative contracts to mitigate the effects of interest rate fluctuations. To the extent legal right of offset with a counterparty exists, the Company reports derivative assets and liabilities on a net basis. The Company has exposure to credit risk to the extent the counterparty is unable to satisfy its settlement obligation. The fair value of the Company’s commodity derivative contracts of approximately $708 million at September 30, 2013 includes the following asset values by bank counterparty: Credit Suisse — $174 million; BNP Paribas — $156 million; Wells Fargo — $116 million; JP Morgan — $113 million; Barclays — $112 million; CitiBank - $23 million; Deutsche Bank — $11 million; Toronto Dominion Bank — $2 million; and Union Bank — $1 million. The credit ratings of certain of these banks have been downgraded because of the sovereign debt crisis in Europe. The estimated fair value of our commodity derivative assets has been risk adjusted using a discount rate based upon the respective published credit default swap rates (if available, or if not available, a discount rate based on the applicable Reuters bond rating) at September, 2013 for each of the European and North American banks. We believe that all of these institutions currently are acceptable credit risks.

	The Company records derivative instruments on the consolidated balance sheets as either an asset or liability measured at fair value and records changes in the fair value of derivatives in current earnings as they occur. Changes in the fair value of commodity derivatives are classified as revenues.
Fair Value Measurements	'
	(f) *Fair Value Measurements*

	Authoritative accounting guidance defines fair value, establishes a framework for measuring fair value, and requires disclosures about fair value measurements. This guidance also relates to all nonfinancial assets and liabilities that are not recognized or disclosed on a recurring basis (e.g., those measured at fair value in a business combination, the initial recognition of asset retirement obligations, and impairments of proved oil and gas properties, and other long-lived assets). The fair value is the price that the Company estimates would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. A fair value hierarchy is used to prioritize input to valuation techniques used to estimate fair value. An asset or liability subject to the fair value requirements is categorized within the hierarchy 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 in its entirety requires judgment and considers factors specific to the asset or liability. The highest priority (Level 1) is given to unadjusted quoted market prices in active markets for identical assets or liabilities, and the lowest priority (Level 3) is given to unobservable inputs. Level 2 inputs are data, other than quoted prices included within Level 1, that are observable for the asset or liability, either directly or indirectly. Instruments that are valued using Level 2 inputs include nonexchange traded derivatives, such as over-the-counter commodity price swaps, basis swaps, and interest rate swaps. Valuation models used to measure fair value of these instruments consider various Level 2 inputs including (i) quoted forward prices for commodities, (ii) time value, (iii) quoted forward interest rates, (iv) current market prices and contractual prices for the underlying instruments, (v) risk of nonperformance by the Company and the counterparty, and (vi) other relevant economic measures. To the extent a legal right of offset with a counterparty exists, the derivative assets and liabilities are reported on a net basis.
Income Taxes	'
	(g) *Income Taxes*

	Prior to the merger described in Note 1, Antero Resources LLC and its subsidiaries filed separate federal and state income tax returns. Antero Resources LLC was a partnership for income tax purposes and therefore is not subject to federal or state income taxes. The tax on the income of Antero Resources LLC was borne by the individual members through the allocation of taxable income.

	Antero Resources Corporation and its subsidiaries recognize deferred tax assets and liabilities for temporary differences resulting from net operating loss carryforwards for income tax purposes and the differences between the financial statement and tax basis of assets and liabilities. The effect of changes in the tax laws or tax rates is recognized in income in the period such changes are enacted. Deferred tax assets are reduced by a valuation allowance, when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized.

	Unrecognized tax benefits represent potential future tax obligations for uncertain tax positions taken on previously filed tax returns that may not ultimately be sustained. The Company recognizes interest expense related to unrecognized tax benefits in interest expense and fines and penalties as income tax expense. The tax years 2009 through 2012 remain open to examination by the U.S. Internal Revenue Service. The Company files tax returns with various state taxing authorities which remain open to examination for tax years 2008 through 2012.
Impairment of Unproved Properties	'
	(h) *Impairment of Unproved Properties*

	Unproved properties are assessed for impairment on a property-by-property basis, and any impairment in value is charged to expense. Impairment is assessed based on remaining lease terms, drilling results, reservoir performance, commodity price outlooks, and future plans to develop acreage.

	Impairment of unproved properties during the three months ended September 30, 2012 and 2013 was $2 million and $3 million, respectively. Impairment of unproved properties during the nine months ended September 30, 2012 and 2013 was $5 million and $10 million, respectively.
Industry Segment and Geographic Information	'
	(i) *Industry Segment and Geographic Information*

	We have evaluated how the Company is organized and managed and have identified one operating segment — the exploration and production of oil, natural gas, and natural gas liquids. We consider our gathering, processing, and marketing functions as ancillary to our oil and gas producing activities. All of our assets are located in the United States and all of our revenues are attributable to United States customers.
Guarantees	'
	(j) *Guarantees*

	In November 2009 and January 2010, an indirect wholly owned finance subsidiary of Antero Resources LLC, Antero Finance, issued $375 million and $150 million, respectively, of 9.375% senior notes due December 1, 2017. In August 2011, Antero Finance issued $400 million of 7.25% senior notes due August 1, 2019. In November 2012 and February 2013, Antero Finance issued $300 million and $225 million, respectively, of 6.00% senior notes due December 1, 2020. For purposes of this footnote, we collectively refer to the 2017 senior notes, the 2019 senior notes and the 2020 senior notes as the “senior notes.”

	Antero Resources LLC, as the parent company (for purposes of this footnote only, the Parent Company), has no independent assets or operations. Antero Finance is a 100% indirectly owned finance subsidiary of Parent Company. The senior notes are each guaranteed on a senior unsecured basis by Parent Company and all of Parent Company’s wholly owned subsidiaries (other than Antero Finance) and certain of its future restricted subsidiaries. The guarantees are full and unconditional and joint and several. The guarantor subsidiaries may be released from those guarantees upon the occurrence of certain events, including (i) the designation of that subsidiary guarantor as an unrestricted subsidiary; (ii) the release or discharge of any guarantee or indebtedness that resulted in the creation of the guarantee of the senior notes by such subsidiary guarantor; or (iii) the sale or other disposition, including the sale of substantially all of the assets, of that subsidiary guarantor. There are no significant restrictions on Antero Finance’s ability to obtain funds from the Parent Company or the subsidiary guarantors by dividend or loan, except those imposed by applicable law. However, the indentures governing the senior notes and the Credit Facility agreement contain significant restrictions on the ability of Antero Finance or the subsidiary guarantors to make distributions to the Parent Company. Finally, the Parent Company’s wholly owned subsidiaries do not have restricted assets that exceed 25% of net assets as of the most recent fiscal year end that may not be transferred to the Parent Company in the form of loans, advances or cash dividends by the subsidiaries without the consent of a third party.

Sale_of_Piceance_and_Arkoma_Pr1

Sale of Piceance and Arkoma Properties - Discontinued Operations (Tables)	9 Months Ended
	Sep. 30, 2013
Sale of Piceance and Arkoma Properties - Discontinued Operations	'
Schedule of results of operations for the Piceance Basin and Arkoma Basin assets shown as discontinued operations on the accompanying Consolidated Statement of Operations and Comprehensive Income (Loss)	'
	Results of operations for the three months and nine months ended September 30, 2012 for the Piceance Basin and Arkoma Basin assets are shown as discontinued operations on the accompanying Consolidated Statement of Operations and Comprehensive Income (Loss) and are comprised of the following (in thousands):

		Three months			Nine months
		Ended			ended
		September 30, 2012			September 30, 2012
	Sales of oil, natural gas, and natural gas liquids	$	22,690		105,096
	Commodity derivative fair value gains (losses)	(18,880		)	46,358
	Total revenues	3,810			151,454
	Lease operating expenses	2,430			16,395
	Gathering, compression, and transportation	7,685			38,210
	Production taxes	1,776			4,874
	Exploration expenses	95			507
	Impairment of unproved properties	(31		)	962
	Depletion, depreciation, and amortization	14,197			77,344
	Accretion of asset retirement obligations	91			310
	Loss on sale of discontinued operations	—			427,232
	Total expenses	26,243			565,834
	Loss from discontinued operations before income taxes	(22,433		)	(414,380	)
	Income tax (expense) benefit	8,642			(4,085	)
	Net loss from discontinued operations attributable to Antero equity owners	$	(13,791	)	(418,465	)

Longterm_Debt_Tables

Long-term Debt (Tables)	9 Months Ended
	Sep. 30, 2013
Long-term Debt	'
Schedule of long-term debt	'
	Long-term debt consists of the following at December 31, 2012 and September 30, 2013 (in thousands):

		December 31,		September 30,
		2012		2013
	Bank credit facility (a)	$	217,000	1,512,500
	9.375% senior notes due 2017 (b)	525,000		525,000
	7.25% senior notes due 2019 (c)	400,000		400,000
	6.00% senior notes due 2020 (d)	300,000		525,000
	9.00% senior note (d)	25,000		25,000
	Net premium	2,058		7,955
		1,469,058		2,995,455
	Less amounts due within one year	25,000		25,000
	Total	$	1,444,058	2,970,455

	(a) *Bank Credit Facility*

	The Company has a senior secured revolving bank credit facility (the Credit Facility) with a consortium of bank lenders. The maximum amount of the Credit Facility is $2.5 billion. Borrowings under the Credit Facility are subject to borrowing base limitations based on the collateral value of the Company’s proved properties and commodity hedge positions and are subject to regular semiannual redeterminations. At September 30, 2013, the borrowing base is $2.0 billion and lender commitments were $1.75 billion. Lender commitments can be increased to the full amount of the borrowing base upon approval of the lenders. The next redetermination of the borrowing base is scheduled to occur in April 2014. The maturity date of the Credit Facility is May 12, 2016. Subsequent to September 30, 2013, lender commitments under the Credit Facility were reduced to $1.5 billion.

	The Credit Facility is secured by mortgages on substantially all of the Company’s properties and guarantees from the Company’s operating subsidiaries. The Credit Facility contains certain covenants, including restrictions on indebtedness and dividends, and requirements with respect to working capital and interest coverage ratios. Interest is payable at a variable rate based on LIBOR or the prime rate based on the Company’s election at the time of borrowing. The Company was in compliance with all of the financial covenants under the Credit Facility as of December 31, 2012 and September 30, 2013.

	As of September 30, 2013, the Company had an outstanding balance under the Credit Facility of $1.5 billion, with a weighted average interest rate of 2.3%, and outstanding letters of credit of approximately $32 million. As of December 31, 2012, the Company had an outstanding balance under the Credit Facility of $217 million, with a weighted average interest rate of 1.91%, and outstanding letters of credit of approximately $43 million. Commitment fees on the unused portion of the Credit Facility are due quarterly at rates ranging from 0.375% to 0.50% of the unused facility based on utilization.

	(b) *9.375% Senior Notes Due 2017*

	On November 17, 2009 Antero Finance issued $375 million of 9.375% senior notes due December 1, 2017 at a discount of $2.6 million. In January 2010, the Company issued an additional $150 million of the same series of 9.375% senior notes at a premium of $6.0 million. The notes are unsecured and effectively subordinated to the Company’s Credit Facility to the extent of the value of the collateral securing the Credit Facility. The notes are guaranteed on a full and unconditional basis and joint and severally by the Company, all of its wholly owned subsidiaries (other than Antero Finance), and certain of its future restricted subsidiaries. Interest on the notes is payable on June 1 and December 1 of each year. Antero Finance may redeem all or part of the notes at any time on or after December 1, 2013 at redemption prices ranging from 104.688% on or after December 1, 2013 to 100% on or after December 1, 2015. At any time prior to December 1, 2013, Antero Finance may also redeem the notes, in whole or in part, at a price equal to 100% of the principal amount of the notes plus a “make-whole” premium. If the Company undergoes a change of control, Antero Finance may be required to offer to purchase notes from the holders.

	The 9.375% senior notes due 2017 will be redeemed with the proceeds of the issuance of the 5.375% notes issued subsequent to September 30, 2013. See Note 11.

	(c) *7.25% Senior Notes Due 2019*

	On August 1, 2011, Antero Finance issued $400 million of 7.25% senior notes due August 1, 2019 at par. The notes are unsecured and effectively subordinated to the Company’s Credit Facility to the extent of the value of the collateral securing the Credit Facility. The notes rank pari passu to the existing 9.375% senior notes. The notes are guaranteed on a senior unsecured basis by the Company, all of its wholly owned subsidiaries (other than Antero Finance), and certain of its future restricted subsidiaries. Interest on the notes is payable on August 1 and February 1 of each year. Antero Finance may redeem all or part of the notes at any time on or after August 1, 2014 at redemption prices ranging from 105.438% on or after August 1, 2014 to 100% on or after August 1, 2017. In addition, on or before August 1, 2014, Antero Finance may redeem up to 35% of the aggregate principal amount of the notes with the net cash proceeds of certain equity offerings, if certain conditions are met, at a redemption price of 107.25% of the principal amount of the notes, plus accrued interest. At any time prior to August 1, 2014, Antero Finance may redeem the notes, in whole or in part, at a price equal to 100% of the principal amount of the notes plus a “make-whole” premium and accrued interest. If the Company undergoes a change of control, the note holders will have the right to require Antero Finance to repurchase all or a portion of the notes at a price equal to 101% of the principal amount of the notes, plus accrued interest.

	The Company will redeem 35% of the 7.25% senior notes due 2019 from the proceeds of the initial public offering. See Note 11.

	(d) *6.00% Senior Notes Due 2020*

	On November 19, 2012, Antero Finance issued $300 million of 6.00% senior notes due December 1, 2020 at par. In a subsequent transaction, on February 4, 2013 Antero Finance issued an additional $225 million of the 6.00% notes at 103% of par. The notes are unsecured and effectively subordinated to the Company’s Credit Facility to the extent of the value of the collateral securing the Credit Facility. The notes rank pari passu to the existing 9.375% and 7.25% senior notes. The notes are guaranteed on a senior unsecured basis by the Company, all of its wholly owned subsidiaries (other than Antero Finance), and certain of its future restricted subsidiaries. Interest on the notes is payable on June 1 and December 1 of each year. Antero Finance may redeem all or part of the notes at any time on or after December 1, 2015 at redemption prices ranging from 104.50% on or after December 1, 2015 to 100% on or after December 1, 2018. In addition, on or before December 1, 2015, Antero Finance may redeem up to 35% of the aggregate principal amount of the notes with the net cash proceeds of certain equity offerings, if certain conditions are met, at a redemption price of 106.00% of the principal amount of the notes, plus accrued interest. At any time prior to December 1, 2015, Antero Finance may redeem the notes, in whole or in part, at a price equal to 100% of the principal amount of the notes plus a “make-whole” premium and accrued interest. If a change of control (as defined in the bond indenture) occurs at any time prior to January 1, 2014, Antero Finance may, at its option, redeem all, but not less than all, of the notes at a redemption price equal to 110% of the principal amount of the notes, plus accrued interest. If the Company undergoes a change of control, the note holders will have the right to require Antero Finance to repurchase all or a portion of the notes at a price equal to 101% of the principal amount of the notes, plus accrued interest.

	(e) *9.00% Senior Note*

	The Company assumed a $25 million unsecured note payable in a business acquisition consummated on December 1, 2010. The note bears interest at 9% and is due December 1, 2013.

	(f) *Treasury Management Facility*

	The Company has a stand-alone revolving note with a lender under the Credit Facility which provides for up to $25 million of cash management obligations in order to facilitate the Company’s daily treasury management. Borrowings under the revolving note are secured by the collateral for the revolving credit facility. Borrowings under the facility bear interest at the lender’s prime rate plus 1.0%. The note matures on June 1, 2014. At December 31, 2012 and September 30, 2013, there were no outstanding borrowings under this facility.

Ownership_Structure_Tables

Ownership Structure (Tables)	9 Months Ended
Ownership Structure (Tables)	Sep. 30, 2013
Ownership Structure	'
Schedule of the outstanding units	'


		Units
		Authorized
		and issued
	Class I units	107,281,058
	Class A and B units	40,007,463
	Class A and B profits units	19,726,873
		167,015,394

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	9 Months Ended
	Sep. 30, 2013
Asset Retirement Obligations	'
Schedule of reconciliation of asset retirement obligations included in other long-term liabilities	'
	The following is a reconciliation of the Company’s asset retirement obligations, included in other long-term liabilities on the condensed consolidated balance sheets, for the nine months ended September 30, 2013 (in thousands):

	Asset retirement obligations — beginning of period	$	10,552
	Obligations incurred	69
	Accretion expense	797
	Asset retirement obligations — end of period	$	11,418

Derivative_Instruments_and_Ris1

Derivative Instruments and Risk Management Activities (Tables)	9 Months Ended
	Sep. 30, 2013
Derivative Instruments and Risk Management Activities	'
Schedule of outstanding commodity derivatives	'


		MMbtu/day		Bbls/day		Price
	Three Months ending December 31, 2013:
	CGTAP-TCO	260,000				$	4.56
	Dominion South	190,844				4.89
	NYMEX-WTI	—		4,300		103.97
	2013 Total	450,844		4,300
	Year ending December 31, 2014:
	CGLA	10,000				$	3.87
	CGTAP-TCO	210,000				5.11
	Dominion South	160,000				5.15
	NYMEX	120,000				4
	NYMEX-WTI	—		3,000		96.53
	2014 Total	500,000		3,000
	Year ending December 31, 2015:
	CGLA	40,000				$	4
	CGTAP-TCO	130,000				4.93
	Dominion South	230,000				5.6
	NYMEX	80,000				4.1
	2015 Total	480,000
	Year ending December 31, 2016:
	CGLA	170,000				$	4.09
	CGTAP-TCO	80,000				4.67
	Dominion South	272,500				5.35
	NYMEX	60,000				4.25
	2016 Total	582,500
	Year ending December 31, 2017:
	CGLA	420,000				$	4.27
	NYMEX	220,000				4.44
	CCG	70,000				4.57
	CGTAP-TCO	20,000				4.02
	2017 Total	730,000
	Year ending December 31, 2018:
	NYMEX	530,000				$	4.73
	Year ending December 31, 2019:
	NYMEX	87,500				$	4.75
Summary of the fair values of derivative instruments, which are not designated as hedges for accounting purposes	'
	The following is a summary of the fair values of our derivative instruments, which are not designated as hedges for accounting purposes and where such values are recorded in the consolidated balance sheets as of December 31, 2012 and September 30, 2013 (in thousands):

		December 31, 2012					September 30, 2013
		Balance					Balance
		sheet					sheet
		location		Fair value			location	Fair value
	Asset derivatives not designated as hedges for accounting purposes:
	Commodity contracts	Current assets		$	160,579		Current assets	$	204,857
	Commodity contracts	Long-term assets		371,436			Long-term assets	503,666
	Total asset derivatives			532,015				708,523
	Liability derivatives not designated as hedges for accounting purposes:
	Commodity contracts	Current liabilities		—			Current liabilities	309
	Net asset fair value of derivatives			$	532,015			$	708,214
Summary of realized and unrealized gains (losses) on derivative instruments	'
	The following is a summary of realized and unrealized gains (losses) on derivative instruments and where such values are recorded in the consolidated statements of operations for the three months ended and nine months ended September 30, 2012 and 2013 (in thousands):

		Statement of		Three months ended				Nine months ended
		operations		September 30,				September 30,
		location		2012			2013	2012		2013
	Commodity derivative fair value gains (losses)	Revenue		$	(159,004	)	161,968	52,210		285,510
	Commodity derivative fair value gains (losses)	Discontinued operations		(18,880		)	—	46,358		—
	Total gains (losses) on commodity contracts			$	(177,884	)	161,968	98,568		285,510
Summary of the valuation of investments and financial instruments by the fair value hierarchy	'
	The following table summarizes the valuation of investments and financial instruments by the fair value hierarchy described in note 1 at September 30, 2013 (in thousands):

		Fair value measurements using
		Quoted
		prices
		in active			Significant
		markets for			other		Significant
		identical			observable		unobservable
		assets			inputs		inputs
	Description	(Level 1)			(Level 2)		(Level 3)	Total
	Net derivatives asset:
	Fixed price commodity swaps	$	—		708,214		—	708,214

Schedule of gross amounts of recognized derivative assets and liabilities, the amounts offset under netting arrangements with counterparties, and the resulting net amounts	'
	The following tables present the gross amounts of recognized derivative assets and liabilities, the amounts offset under netting arrangements with counterparties, and the resulting net amounts presented in the condensed consolidated balance sheets for the periods presented, all at fair value (in thousands):

		December 31, 2012						September 30, 2013
												Net amounts
							Net amounts					of assets
		Gross amounts			Gross amounts		of assets	Gross amounts		Gross amounts		(liabilities)
		of recognized			offset on		on balance	of recognized		offset on		on balance
		assets			balance sheet		sheet	assets		balance sheet		sheet
	Commodity derivative assets	$	597,359		(65,344	)	532,015	715,960		(7,437	)	708,523
	Commodity derivative liabilities	—			—		—	—		(309	)	(309	)

Business_and_Organization_Deta

Business and Organization (Details) (USD $)	3 Months Ended		9 Months Ended		0 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Oct. 16, 2013	Oct. 16, 2013	Oct. 16, 2013	Oct. 16, 2013
					Subsequent event	Subsequent event	Subsequent event	Subsequent event
						Forecast	ARC	Merger agreement
								ARC
Business and Organization	'	'	'	'	'	'	'	'
Number of shares of common stock issued upon conversion of membership interest held by subsidiary	'	'	'	'	'	'	'	224,375,000
Number of additional shares of common stock issued	'	'	'	'	'	'	37,674,659	'
Estimated net proceeds from issuance of additional shares of common stock	'	'	'	'	'	'	$1,580,000,000	'
Non-cash stock compensation expense expected to be recognized in the fourth quarter of 2013	'	'	'	'	'	297,000,000	'	'
Additional stock compensation to be recognized over the remaining service period	'	'	'	'	$217,000,000	'	'	'
Basic shares outstanding upon the public offering	262,050,000	262,050,000	262,050,000	262,050,000	'	'	'	'
Diluted shares outstanding upon the public offering	262,050,000	262,050,000	262,050,000	262,050,000	'	'	'	'

Basis_of_Presentation_and_Sign2

Basis of Presentation and Significant Accounting Policies (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
	Sep. 30, 2013	Sep. 30, 2012	item	Sep. 30, 2012
Basis of Presentation and Significant Accounting Policies	'	'	'	'
Other comprehensive income (loss)	'	'	$0	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	708,000,000	'	708,000,000	'
Impairment of Unproved Properties	'	'	'	'
Impairment of unproved properties	3,000,000	2,000,000	10,000,000	5,000,000
Industry Segment and Geographic Information	'	'	'	'
Number of operating segments	'	'	1	'
BNP Paribas	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	156,000,000	'	156,000,000	'
Credit Suisse	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	174,000,000	'	174,000,000	'
Wells Fargo	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	116,000,000	'	116,000,000	'
JP Morgan	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	113,000,000	'	113,000,000	'
Barclays	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	112,000,000	'	112,000,000	'
Citi Bank	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	23,000,000	'	23,000,000	'
Deutsche Bank	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	11,000,000	'	11,000,000	'
Union Bank	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	1,000,000	'	1,000,000	'
Toronto Dominion Bank	'	'	'	'
Derivative Financial Instruments	'	'	'	'
Fair value of commodity derivative contracts	$2,000,000	'	$2,000,000	'

Basis_of_Presentation_and_Sign3

Basis of Presentation and Significant Accounting Policies (Details 2) (USD $)

Sep. 30, 2013

Dec. 31, 2012

Jan. 31, 2010

Nov. 30, 2009

Sep. 30, 2013

Dec. 31, 2012

Aug. 31, 2011

Sep. 30, 2013

Dec. 31, 2012

Feb. 04, 2013

Nov. 19, 2012

Sep. 30, 2013

In Millions, unless otherwise specified

Antero Finance

Antero Resources LLC

9.375% senior notes due 2017

7.25% senior notes due 2019

6.00% senior notes due 2020

Antero Finance

Guarantees

Senior notes issued

$150

$375

$400

$225

$300

Interest rate (as a percent)

9.38%

7.25%

6.00%

Amount of independent assets

Amount of independent operations

Ownership percentage

100.00%

Restricted assets of wholly owned subsidiaries as percentage of net assets considered for transfer to the parent company, maximum

25.00%

Sale_of_Piceance_and_Arkoma_Pr2

Sale of Piceance and Arkoma Properties - Discontinued Operations (Details) (USD $)

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

3 Months Ended

0 Months Ended

3 Months Ended

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. 21, 2012

Dec. 31, 2012

Jun. 29, 2012

Jun. 30, 2012

Piceance Basin and Arkoma Basin

Piceance Basin

Arkoma properties

Sale of Assets

Net proceeds from the sale adjusted for expenses of the sale and estimated income, expenses, and capital costs

$316,000,000

$427,000,000

Sale consideration

325,000,000

445,000,000

Term of post-closing adjustments which would effect the agreement to sell the properties

'1 year

'2 years

Loss on sale

-5,000,000

427,232,000

364,000,000

Obligation assumed by purchaser

100,000,000

Proceeds from liquidation of hedge positions

100,000,000

Loss on sale of assets

427,000,000

Pre-tax income received from sales tax refund and reductions in estimated expenses

5,000,000

Income received from sales tax refund and reductions in estimated expenses, net of tax

3,100

Results of operations and the loss on the sale of the assets

Sales of oil, natural gas, and natural gas liquids

22,690,000

105,096,000

Commodity derivative fair value gains (losses)

161,968,000

-159,004,000

285,510,000

52,210,000

-18,880,000

46,358,000

Total revenue

384,522,000

-92,038,000

833,120,000

500,628,000

3,810,000

151,454,000

Lease operating expenses

2,697,000

1,513,000

5,222,000

4,072,000

2,430,000

16,395,000

Gathering, compression, and transportation

58,383,000

25,291,000

148,023,000

56,945,000

7,685,000

38,210,000

Production taxes

11,851,000

3,621,000

30,578,000

10,734,000

1,776,000

4,874,000

Exploration expenses

5,372,000

3,156,000

17,034,000

7,912,000

95,000

507,000

Impairment of unproved properties

3,205,000

2,438,000

9,564,000

4,019,000

-31,000

962,000

Depletion, depreciation, and amortization

65,697,000

26,858,000

158,650,000

65,289,000

14,197,000

77,344,000

Accretion of asset retirement obligations

266,000

25,000

797,000

71,000

91,000

310,000

Loss (gain) on sale of discontinued operations

-5,000,000

427,232,000

364,000,000

Total operating expenses

161,914,000

74,840,000

410,595,000

180,626,000

26,243,000

565,834,000

Loss from discontinued operations before income taxes

222,608,000

-166,878,000

422,525,000

320,002,000

-22,433,000

-414,380,000

Income tax (expense) benefit

8,642,000

-4,085,000

Net loss from discontinued operations attributable to Antero equity owners

$3,100,000

($13,791,000)

$3,100,000

($418,465,000)

($13,791,000)

($418,465,000)

Longterm_Debt_Details

Long-term Debt (Details) (USD $)

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Jan. 31, 2010

Nov. 30, 2009

Sep. 30, 2013

Nov. 17, 2009

Sep. 30, 2013

Dec. 31, 2012

Aug. 31, 2011

Sep. 30, 2013

Dec. 31, 2012

Feb. 04, 2013

Nov. 19, 2012

Sep. 30, 2013

Dec. 31, 2010

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Nov. 05, 2013

Bank credit facility

9.375% senior notes due 2017

7.25% senior notes due 2019

6.00% senior notes due 2020

9.00% senior note

Net premium

Stand-alone revolving note

5.375% senior notes due 2021

Subsequent event

Minimum

Maximum

Antero Finance

Maximum

Antero Finance

Maximum

Antero Finance

On or after December 1, 2013

On or after December 1, 2015

Prior to December 1, 2013

On or after August 1, 2014

On or after August 1, 2017

On or before August 1, 2014

Antero Finance

On or after December 1, 2015

On or after December 1, 2018

On or before December 1, 2015

Prior to December 1, 2015

Prior to January 1, 2014

Antero Finance

Subsequent event

On or before August 1, 2014

On or before December 1, 2015

Long- term Debt

Long-term debt

$2,995,455,000

$1,469,058,000

$1,512,500,000

$217,000,000

$525,000,000

$400,000,000

$525,000,000

$300,000,000

$25,000,000

$7,955,000

$2,058,000

Less amounts due within one year

25,000,000

Long-term debt

2,970,455,000

1,444,058,000

Interest rate (as a percent)

9.38%

7.25%

6.00%

9.00%

5.38%

Maximum amount of the Credit Facility

2,500,000,000

25,000,000

Current borrowing base

2,000,000,000

Lender commitments

1,750,000,000

1,500,000,000

Outstanding balance

1,500,000,000

217,000,000

Weighted average interest rate (as a percent)

2.30%

1.91%

Outstanding letters of credit

32,000,000

43,000,000

Commitment fees on the unused portion (as a percent)

0.38%

0.50%

Senior notes issued

150,000,000

375,000,000

400,000,000

225,000,000

300,000,000

1,000,000,000

Issue price as percentage of par value

103.00%

Discount on long-term debt

2,600,000

Premium on long-term debt

6,000,000

Redemption price of the debt instrument in the event of change of control (as a percent)

104.69%

100.00%

105.44%

100.00%

104.50%

100.00%

110.00%

Percentage of the principal amount of the debt instrument which the entity may redeem with the proceeds from certain equity offerings

35.00%

Redemption price of the debt instrument if redeemed with the proceeds of certain equity offerings (as a percent)

107.25%

106.00%

Percentage of principal amount at which notes may be required to be repurchased in event of change of control

101.00%

Description of variable rate basis

'LIBOR or lender's prime rate

'lender's prime rate

Unsecured notes payable assumed in the business acquisition

$25,000,000

Basis spread on variable rate (as a percent)

1.00%

Percentage of the principal amount of the debt instrument which the entity may redeem with the proceeds from initial public offering

35.00%

Ownership_Structure_Details

Ownership Structure (Details) (USD $)	9 Months Ended	12 Months Ended
In Millions, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Ownership Structure	'	'
Units authorized and issued (in shares)	167,015,394	167,015,394
Number of classes of outstanding units not entitled to current cash distributions or are convertible into indebtedness	3	'
Class I units	'	'
Ownership Structure	'	'
Units authorized and issued (in shares)	107,281,058	107,281,058
Special allocation (as a percent)	8.00%	8.00%
Aggregate liquidation priority, including the special allocation	$2,325	$2,191
Class A and B units	'	'
Ownership Structure	'	'
Units authorized and issued (in shares)	40,007,463	40,007,463
Class A and B profit units	'	'
Ownership Structure	'	'
Units authorized and issued (in shares)	19,726,873	19,726,873

Financial_Instruments_Details

Financial Instruments (Details) (Recurring, Level 2 market data, USD $)	Sep. 30, 2013	Dec. 31, 2012
In Billions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Recurring \| Level 2 market data	'	'
Financial Instruments	'	'
Fair value of senior notes	$1.50	$1.30

Asset_Retirement_Obligations_D

Asset Retirement Obligations (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Asset Retirement Obligations	'
Asset retirement obligations - beginning of period	$10,552
Obligations incurred	69
Accretion expense	797
Asset retirement obligations - end of period	$11,418

Derivative_Instruments_and_Ris2

Derivative Instruments and Risk Management Activities (Details) (USD $)	9 Months Ended
	Sep. 30, 2013
	item
Derivative Instruments and Risk Management Activities	'
Amount of collateral from counterparties	$0
Number of derivative positions not secured by collateral	1
Past due receivables from counterparties	0
Past due payables to counterparties	$0

Derivative_Instruments_and_Ris3

Derivative Instruments and Risk Management Activities (Details 2) (Swaps)	Sep. 30, 2013
Natural gas \| Year ending December 31, 2013	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	450,844
Natural gas \| Year ending December 31, 2014	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	500,000
Natural gas \| Year ending December 31, 2015	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	480,000
Natural gas \| Year ending December 31, 2016	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	582,500
Natural gas \| Year ending December 31, 2017	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	730,000
Natural gas \| CGLA \| Year ending December 31, 2014	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	10,000
Weighted average index price	3.87
Natural gas \| CGLA \| Year ending December 31, 2015	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	40,000
Weighted average index price	4
Natural gas \| CGLA \| Year ending December 31, 2016	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	170,000
Weighted average index price	4.09
Natural gas \| CGLA \| Year ending December 31, 2017	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	420,000
Weighted average index price	4.27
Natural gas \| CGTAP-TCO \| Year ending December 31, 2013	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	260,000
Weighted average index price	4.56
Natural gas \| CGTAP-TCO \| Year ending December 31, 2014	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	210,000
Weighted average index price	5.11
Natural gas \| CGTAP-TCO \| Year ending December 31, 2015	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	130,000
Weighted average index price	4.93
Natural gas \| CGTAP-TCO \| Year ending December 31, 2016	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	80,000
Weighted average index price	4.67
Natural gas \| CGTAP-TCO \| Year ending December 31, 2017	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	20,000
Weighted average index price	4.02
Natural gas \| Dominion South \| Year ending December 31, 2013	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	190,844
Weighted average index price	4.89
Natural gas \| Dominion South \| Year ending December 31, 2014	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	160,000
Weighted average index price	5.15
Natural gas \| Dominion South \| Year ending December 31, 2015	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	230,000
Weighted average index price	5.6
Natural gas \| Dominion South \| Year ending December 31, 2016	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	272,500
Weighted average index price	5.35
Natural gas \| NYMEX-WTI \| Year ending December 31, 2013	'
Commodity Derivatives	'
Weighted average index price	103.97
Natural gas \| NYMEX-WTI \| Year ending December 31, 2014	'
Commodity Derivatives	'
Weighted average index price	96.53
Natural gas \| NYMEX \| Year ending December 31, 2014	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	120,000
Weighted average index price	4
Natural gas \| NYMEX \| Year ending December 31, 2015	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	80,000
Weighted average index price	4.1
Natural gas \| NYMEX \| Year ending December 31, 2016	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	60,000
Weighted average index price	4.25
Natural gas \| NYMEX \| Year ending December 31, 2017	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	220,000
Weighted average index price	4.44
Natural gas \| NYMEX \| Year ending December 31, 2018	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	530,000
Weighted average index price	4.73
Natural gas \| NYMEX \| Year ending December 31, 2019	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	87,500
Weighted average index price	4.75
Natural gas \| CCG \| Year ending December 31, 2017	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	70,000
Weighted average index price	4.57
Oil \| Year ending December 31, 2013	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	4,300
Oil \| Year ending December 31, 2014	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	3,000
Oil \| NYMEX-WTI \| Year ending December 31, 2013	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	4,300
Oil \| NYMEX-WTI \| Year ending December 31, 2014	'
Commodity Derivatives	'
Notional amount (MMBtu/Bbls per day)	3,000

Derivative_Instruments_and_Ris4

Derivative Instruments and Risk Management Activities (Details 3) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair value of derivative instruments	'	'
Current portion of fair value of derivative assets	$204,857	$160,579
Noncurrent portion of fair value of derivative assets	503,666	371,436
Current portion of fair value of derivative liability	309	'
Commodity contracts	'	'
Fair value of derivative instruments	'	'
Net amounts of assets on balance sheet	708,214	532,015
Derivatives not designated as hedges for accounting purposes \| Commodity contracts	'	'
Fair value of derivative instruments	'	'
Current portion of fair value of derivative assets	204,857	160,579
Noncurrent portion of fair value of derivative assets	503,666	371,436
Net amounts of assets on balance sheet	708,523	532,015
Current portion of fair value of derivative liability	$309	'

Derivative_Instruments_and_Ris5

Derivative Instruments and Risk Management Activities (Details 4) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Summary of realized and unrealized gains (losses) on derivative instruments	'	'	'	'
Total gains (losses) on commodity contracts	$161,968	($177,884)	$285,510	$98,568
Revenue	'	'	'	'
Summary of realized and unrealized gains (losses) on derivative instruments	'	'	'	'
Commodity derivative fair value gains (losses)	161,968	-159,004	285,510	52,210
Discontinued operations	'	'	'	'
Summary of realized and unrealized gains (losses) on derivative instruments	'	'	'	'
Commodity derivative fair value gains (losses)	'	($18,880)	'	$46,358

Derivative_Instruments_and_Ris6

Derivative Instruments and Risk Management Activities (Details 5) (USD $)	Sep. 30, 2013
In Thousands, unless otherwise specified	Sep. 30, 2013
Net derivatives asset:	'
Fixed price derivative assets	$708,000
Significant other observable inputs (Level 2) \| Commodity swaps	'
Net derivatives asset:	'
Fixed price derivative assets	708,214
Total \| Commodity swaps	'
Net derivatives asset:	'
Fixed price derivative assets	$708,214

Derivative_Instruments_and_Ris7

Derivative Instruments and Risk Management Activities (Details 6) (Commodity derivative, USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Commodity derivative	'	'
Commodity derivative assets	'	'
Gross amounts of recognized assets	$715,960	$597,359
Gross amounts offset on balance sheet	-7,437	-65,344
Net amounts of assets on balance sheet	708,214	532,015
Commodity derivative liabilities	'	'
Gross amounts offset on balance sheet	-309	'
Net amounts of assets (liabilities) on balance sheet	($309)	'

Sale_of_Appalachian_Gathering_1

Sale of Appalachian Gathering Assets (Details) (USD $)	3 Months Ended	1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Mar. 31, 2012	Mar. 31, 2012	Sep. 30, 2013	Mar. 26, 2012	Sep. 30, 2013
		Appalachian Gathering Assets	Appalachian Gathering Assets	Appalachian Gathering Assets	Appalachian Gathering Assets	Appalachian Gathering Assets
		acre			acre	Maximum
		mi
Sale of Assets	'	'	'	'	'	'
Period of exclusive rights to gather the gas within AOD	'	'20 years	'	'	'	'
Sale consideration	'	$375,000,000	'	'	'	'
Area of low pressure pipeline systems and gathering rights sold (in miles)	'	25	'	'	'	'
Area of land held (in acres)	'	'	'	'	104,000	'
Area of AOD (in acres)	'	250,000	'	'	'	'
Period for which entity is committed to deliver minimum volumes into gathering systems, with certain carryback and carryforward adjustments for overages or deficiencies	'	'	'	'7 years	'	'
Additional sale proceeds on meeting certain volume threshold	'	'	'	'	'	40,000,000
Earn out period	'	'	'	'3 years	'	'
Gain recognized on the sale of assets	($115,000)	'	$291,000,000	'	'	'

Subsequent_Events_Details

Subsequent Events (Details) (USD $)

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Jan. 31, 2010

Nov. 30, 2009

Sep. 30, 2013

Aug. 31, 2011

Sep. 30, 2013

Feb. 04, 2013

Nov. 19, 2012

Sep. 30, 2013

Oct. 16, 2013

Nov. 05, 2013

5.375% senior notes due 2021

9.375% senior notes due 2017

7.25% senior notes due 2019

6.00% senior notes due 2020

9.00% senior note

Antero Finance

Subsequent event

9.375% senior notes due 2017

7.25% senior notes due 2019

6.00% senior notes due 2020

Initial Public Offering

Antero Finance

5.375% senior notes due 2021

On or after November 1, 2016

On or after November 1, 2019

On or before November 1, 2016

Prior to November 1, 2016

Prior to May 1, 2015

Maximum

Subsequent Event

Common stock issued (in shares)

41,083,750

Shares issued on exercise of option by underwriters for purchase from selling stockholder

3,409,091

Shares issued on exercise of option by underwriters

1,949,659

Sale of common stock (in shares)

37,674,659

Net proceeds from sale of shares of common stock

$1,580,000,000

Senior notes issued

$150,000,000

$375,000,000

$400,000,000

$225,000,000

$300,000,000

$1,000,000,000

Interest rate (as a percent)

5.38%

9.38%

7.25%

6.00%

9.00%

9.38%

7.25%

6.00%

5.38%

Redemption price of the debt instrument in the event of change of control (as a percent)

104.03%

100.00%

110.00%

Percentage of the principal amount of the debt instrument which the entity may redeem with the proceeds from certain equity offerings

35.00%

Redemption price of the debt instrument if redeemed with the proceeds of certain equity offerings (as a percent)

105.38%

Percentage of principal amount at which notes may be required to be repurchased in event of change of control

101.00%