Alta Mesa 10-Q 13 Aug 14 2014 Q2 Quarterly report Financial data

Document_And_Entity_Informatio

Document And Entity Information	6 Months Ended
	Jun. 30, 2014
Document And Entity Information [Abstract]	'
Entity Registrant Name	'Alta Mesa Holdings, LP
Entity Central Index Key	'0001518403
Document Type	'10-Q
Document Period End Date	30-Jun-14
Amendment Flag	'false
Document Fiscal Year Focus	'2014
Document Fiscal Period Focus	'Q2
Current Fiscal Year End Date	'--12-31
Entity Filer Category	'Non-accelerated Filer
Entity Common Stock, Shares Outstanding	0

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
CURRENT ASSETS	'	'
Cash and cash equivalents	$8,366	$6,537
Accounts receivable, net	52,233	43,486
Other receivables	1,033	2,552
Prepaid expenses and other current assets	3,489	3,077
Derivative financial instruments	477	5,572
TOTAL CURRENT ASSETS	65,598	61,224
PROPERTY AND EQUIPMENT	'	'
Oil and natural gas properties, successful efforts method, net	669,180	691,770
Other property and equipment, net	9,629	9,100
TOTAL PROPERTY AND EQUIPMENT, NET	678,809	700,870
OTHER ASSETS	'	'
Investment in Partnership - cost	9,000	9,000
Deferred financing costs, net	9,510	10,943
Derivative financial instruments	'	3,405
Advances to operators	3,148	6,863
Deposits and other assets	1,144	1,186
TOTAL OTHER ASSETS	22,802	31,397
TOTAL ASSETS	767,209	793,491
CURRENT LIABILITIES	'	'
Accounts payable and accrued liabilities	109,520	96,095
Current portion, asset retirement obligations	6,450	3,844
Derivative financial instruments	15,967	4,483
TOTAL CURRENT LIABILITIES	131,937	104,422
LONG-TERM LIABILITIES	'	'
Asset retirement obligations, net of current portion	53,346	52,179
Long-term debt	677,353	766,868
Notes payable to founder	23,931	23,331
Derivative financial instruments	15,369	4,486
Other long-term liabilities	7,299	2,312
TOTAL LONG-TERM LIABILITIES	777,298	849,176
TOTAL LIABILITIES	909,235	953,598
COMMITMENTS AND CONTINGENCIES (NOTE10)	'	'
PARTNERS' CAPITAL (DEFICIT)	-142,026	-160,107
TOTAL LIABILITIES AND PARTNERS' CAPITAL (DEFICIT)	$767,209	$793,491

Consolidated_Statements_Of_Ope

Consolidated Statements Of Operations (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
REVENUES	'	'	'	'
Oil	$92,586	$75,455	$172,328	$140,110
Natural gas	17,855	17,580	36,540	31,182
Natural gas liquids	4,924	3,963	9,866	7,024
Other revenues	225	506	288	1,158
Total	115,590	97,504	219,022	179,474
Gain (loss) on sale of oil and gas property	-4,607	-120	68,551	-1,190
Gain (loss) --- oil and natural gas derivative contracts	-24,729	26,147	-35,428	13,825
TOTAL REVENUES	86,254	123,531	252,145	192,109
EXPENSES	'	'	'	'
Lease and plant operating expense	17,528	18,067	36,582	33,650
Production and ad valorem taxes	6,952	7,452	14,628	13,196
Workover expense	2,198	4,508	4,963	8,585
Exploration expense	18,757	6,270	28,236	8,866
Depreciation, depletion, and amortization expense	33,198	28,375	62,477	52,880
Impairment expense	18,300	19,191	19,202	26,546
Accretion expense	613	449	1,171	892
General and administrative expense	13,894	9,420	38,611	18,761
TOTAL EXPENSES	111,440	93,732	205,870	163,376
INCOME (LOSS) FROM OPERATIONS	-25,186	29,799	46,275	28,733
OTHER INCOME (EXPENSE)	'	'	'	'
Interest expense	-13,632	-13,659	-27,920	-26,949
Interest income	6	28	9	98
TOTAL OTHER INCOME (EXPENSE)	-13,626	-13,631	-27,911	-26,851
INCOME (LOSS) BEFORE STATE INCOME TAXES	-38,812	16,168	18,364	1,882
BENEFIT FROM (PROVISION FOR) STATE INCOME TAXES	'	'	-283	'
NET INCOME (LOSS)	($38,812)	$16,168	$18,081	$1,882

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
CASH FLOWS FROM OPERATING ACTIVITIES:	'	'
Net income (loss)	$18,081	$1,882
Adjustments to reconcile net income (loss) to net cash provided by operating activities:	'	'
Depreciation, depletion, and amortization expense	62,477	52,880
Impairment expense	19,202	26,546
Accretion expense	1,171	892
Amortization of loan costs	1,433	1,409
Amortization of debt discount	255	255
Dry hole expense	20,120	4,108
Expired leases	359	222
(Gain) loss on derivative contracts	35,428	-13,825
Settlements on derivative contracts	-4,561	12,775
Interest converted into debt	600	599
Gain (loss on sale of oil and gas property	-68,551	1,190
Changes in assets and liabilities:	'	'
Restricted cash	'	2,305
Accounts receivable	-8,747	-5,791
Other receivables	1,519	-149
Prepaid expenses and other non-current assets	3,345	7,837
Settlement of asset retirement obligation	-1,617	-716
Accounts payable, accrued liabilities, and other long-term liabilities	8,153	-6,327
NET CASH PROVIDED BY OPERATING ACTIVITIES	88,667	86,092
CASH FLOWS FROM INVESTING ACTIVITIES:	'	'
Capital expenditures for property and equipment	-165,165	-173,612
Proceeds from sale of property	168,097	'
NET CASH USED IN INVESTING ACTIVITIES	2,932	-173,612
CASH FLOWS FROM FINANCING ACTIVITIES:	'	'
Proceeds from long-term debt	79,500	89,500
Repayments of long-term debt	-169,270	'
NET CASH PROVIDED BY FINANCING ACTIVITIES	-89,770	89,500
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1,829	1,980
CASH AND CASH EQUIVALENTS, beginning of period	6,537	5,786
CASH AND CASH EQUIVALENTS, end of period	8,366	7,766
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION	'	'
Cash paid during the period for interest	24,964	24,063
Cash paid during the period for state taxes	-125	18
Change in asset retirement obligations	2,838	747
Change in accruals or liabilities for capital expenditures	$11,642	($4,822)

Operations_Consolidation_And_B

Operations, Consolidation And Basis Of Presentation	6 Months Ended
	Jun. 30, 2014
Operations, Consolidation And Basis Of Presentation [Abstract]	'
Operations, Consolidation And Basis Of Presentation	'
	1.  OPERATIONS, CONSOLIDATION AND BASIS OF PRESENTATION
	Alta Mesa Holdings, LP and its subsidiaries (“we,” “us,” “our,” the “Company,” and “Alta Mesa”) is an independent energy company engaged primarily in the acquisition, exploration, development, and production of onshore oil and natural gas properties. Our core properties are located primarily in Texas, Louisiana, and Oklahoma.
	The consolidated financial statements reflect our accounts after elimination of all significant intercompany transactions and balances. The financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in our annual consolidated financial statements for the year ended December 31, 2013, which were filed with the Securities and Exchange Commission in our 2013 Annual Report on Form 10-K.
	The consolidated financial statements included herein as of June 30, 2014, and for the three month and six month periods ended June 30, 2014 and 2013, are unaudited, and in the opinion of management, the information furnished reflects all material adjustments, consisting of normal recurring adjustments, necessary for a fair presentation of consolidated financial position and of the results of operations for the interim periods presented. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. Certain minor reclassifications of prior period consolidated financial statements have been made to conform to current reporting practices. The consolidated results of operations for interim periods are not necessarily indicative of results to be expected for a full year.

Significant_Acquisitions_And_D

Significant Acquisitions And Divestitures	6 Months Ended
	Jun. 30, 2014
Significant Acquisitions And Divestitures [Abstract]	'
Significant Acquisitions And Divestitures	'
	NOTE 3 — SIGNIFICANT ACQUISITIONS AND DIVESTITURES
	Eagleville Divestiture
	On March 25, 2014 we closed the sale of certain of our properties located primarily in Karnes County, Texas to Memorial Production Operating LLC, comprising a portion of our Eagleville field (“Eagleville divestiture”).  The properties sold included a working interest in all of our producing wells as of the effective date of January 1, 2014.  We retained a net profits interest in these wells based on 50% of our original working interest in 2014, declining to 30% in 2015, 15% in 2016, and zero in 2017.  Also included in the sale was a 30% undivided interest in all our Eagleville mineral leases and interests, and 30% of our working interest in all our wells in progress on December 31, 2013 or drilled after January 1, 2014.  The initial cash purchase price was $173 million, subsequently adjusted to approximately $168 million for settlement adjustments through June 30, 2014.  The purchase and sale agreement provides for customary adjustments to the purchase price for revenues and expenses incurred after the effective date.  As of January 1, 2014, estimated net proved reserves associated with the sold portion of these properties were approximately 7.7 MMBOE.  We recorded a preliminary gain on sale from the Eagleville divestiture of $68.7 million during the first half of 2014, based on a preliminary allocation of basis between the properties sold and properties retained.
	The sold portion of Eagleville field contributed approximately $8.6 million and $16.4 million in net pre-tax profit for the three months and six months ended June 30, 2013, respectively, and $6.6 million in the first quarter of 2014, prior to its sale.
	Hilltop Divestiture
	On October 2, 2013 we closed the sale of certain of our properties in East Texas to Cubic Oil, Inc., comprising a portion of our Hilltop field (“Hilltop divestiture”).  The properties sold were primarily producers of dry natural gas located in Leon County, Texas.  As of July 1, 2013, estimated net proved reserves associated with these properties were 11.2 BCFE. The net cash purchase price was approximately $19 million.  There was no material gain on the sale.  These wells contributed approximately $0.2 million in net pre-tax income during the three months ended June 30, 2013 and $0.1 million net pre-tax loss during the six months ended June 30, 2013.
	Weeks Island Acquisition
	On October 1, 2013 we closed a transaction to purchase certain producing properties in South Louisiana from Stone Energy Offshore, L.L.C. (“Stone”) for cash consideration of approximately $45 million plus related abandonment costs, which was later modified through settlement adjustments to approximately $42 million cash. This purchase increased our working interest in our Weeks Island field. Total estimated net proved reserves associated with the acquisition were 1.8 MMBOE as of the effective date of July 1, 2013.
	A summary of the consideration paid and the preliminary allocation of the purchase prices are as follows:
		October 1,
		2013
		(dollars in thousands)
		(unaudited)
	Summary of Consideration
	Cash	$	41,841
	Fair value of asset retirement obligations assumed		5,311
	Total	$	47,152
	Summary of Purchase Price Allocation
	Proved oil and natural gas properties	$	30,279
	Unproved oil and natural gas properties		16,873
	Total	$	47,152
	The revenue and earnings related to the Weeks Island acquisition are included in our consolidated statement of operations for the year ended December 31, 2013 from date of acquisition. The revenue and earnings of the combined entity, had the acquisitions occurred at January 1, 2013, are provided below. This unaudited pro forma information has been derived from historical information and is for illustrative purposes only. The unaudited pro forma financial information does not attempt to predict or suggest future results. It also does not necessarily reflect what the historical results of the combined company would have been had the companies been combined during this period.
		Total
		Revenue		Income
		(dollars in thousands)
		(unaudited)
	Pro forma results for the six months ended June 30, 2013	$	213,283	$	8,625

Property_And_Equipment

Property And Equipment	6 Months Ended
	Jun. 30, 2014
Property And Equipment [Abstract]	'
Property And Equipment	'
	4. PROPERTY AND EQUIPMENT
	Property and equipment consists of the following:
		June 30,		December 31,
		2014		2013
		(dollars in thousands)
		(unaudited)
	OIL AND NATURAL GAS PROPERTIES
	Unproved properties	$	77,094	$	86,721
	Accumulated impairment		-5,191		-7,356
	Unproved properties, net		71,903		79,365
	Proved oil and natural gas properties		1,414,221		1,405,658
	Accumulated depreciation, depletion, amortization and impairment		-816,944		-793,253
	Proved oil and natural gas properties, net		597,277		612,405
	TOTAL OIL AND NATURAL GAS PROPERTIES, net		669,180		691,770
	LAND		1,918		1,418
	OTHER PROPERTY AND EQUIPMENT
	Office furniture and equipment, vehicles		15,012		13,802
	Accumulated depreciation		-7,301		-6,120
	OTHER PROPERTY AND EQUIPMENT, net		7,711		7,682
	TOTAL PROPERTY AND EQUIPMENT, net	$	678,809	$	700,870
	Capitalized exploratory well costs
	Deferred exploratory well costs were $6.5 million and $18.4 million at June 30, 2014 and December 31, 2013, respectively.  The decrease in deferred costs during 2014 is primarily the result of the transfer of $13.5 million for the costs of a New Mexico exploratory well to dry hole expense.  As of June 30, 2014 deferred exploratory well costs include approximately $3.3 million capitalized for greater than one year.

Fair_Value_Disclosures

Fair Value Disclosures	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Disclosures	'
	5. FAIR VALUE DISCLOSURES
	We follow the guidance of ASC 820, “Fair Value Measurements and Disclosures,” in the estimation of fair values. ASC 820 provides a hierarchy of fair value measurements, based on the inputs to the fair value estimation process. It requires disclosure of fair values classified according to defined “levels,” which are based on the reliability of the evidence used to determine fair value, with Level 1 being the most reliable and Level 3 the least reliable. Level 1 evidence consists of observable inputs, such as quoted prices in an active market. Level 2 inputs typically correlate the fair value of the asset or liability to a similar, but not identical item which is actively traded. Level 3 inputs include at least some unobservable inputs, such as valuation models developed using the best information available in the circumstances.
	We utilize the modified Black-Scholes and the Turnbull Wakeman option pricing models to estimate the fair values of oil and natural gas derivative contracts. Inputs to these models include observable inputs from the New York Mercantile Exchange (“NYMEX”) for futures contracts, and inputs derived from NYMEX observable inputs, such as implied volatility of oil and natural gas prices. We have classified the fair values of all our oil and natural gas derivative contracts as Level 2.
	Our senior notes are carried at historical cost, net of amortized discount; we estimate the fair value of the senior notes for disclosure purposes (see Note 2). This estimation is based on the most recent trading values of the notes at or near the reporting dates, which is a Level 1 determination.
	Oil and natural gas properties are subject to impairment testing and potential impairment write down. Oil and gas properties with a carrying amount of $60.3 million were written down to their fair value of $41.1 million, resulting in an impairment charge of $19.2 million for the six months ended June 30,  2014. Oil and gas properties with a carrying amount of $46.5 million were written down to their fair value of $20.0 million, resulting in an impairment charge of $26.5 million for the six months ended June 30, 2013. Oil and gas properties with a carrying amount of $59.1 million were written down to their fair value of $40.8 million, resulting in an impairment charge of $18.3 million for the three months ended June 30, 2014.  For the three months ended June 30, 2013, oil and gas properties with a carrying amount of $35.4 million were written down to their fair value of $16.2 million, resulting in an impairment charge of $19.2 million. Significant Level 3 assumptions used in the calculation of estimated discounted cash flows in the impairment analysis included our estimate of future oil and natural gas prices, production costs, development expenditures, estimated timing of production of proved reserves, appropriate risk-adjusted discount rates, and other relevant data.
	New additions to asset retirement obligations result from estimations for new properties, and fair values for them are categorized as Level 3. Such estimations are based on present value techniques that utilize company-specific information for such inputs as cost and timing of plugging and abandonment of wells and facilities. We recorded $0.4 million and $0.4 million in additions to asset retirement obligations measured at fair value during the six months ended June 30,  2014 and 2013, respectively.
	The following table presents information about our financial assets and liabilities measured at fair value on a recurring basis as of June 30,  2014 and December 31, 2013, and indicates the fair value hierarchy of the valuation techniques we utilized to determine such fair value:
		Level 1		Level 2		Level 3		Total
			(dollars in thousands)
	At June 30, 2014 (unaudited):
	Financial Assets:
	Derivative contracts for oil and natural gas		—	$	19,739		—	$	19,739
	Financial Liabilities:
	Derivative contracts for oil and natural gas		—	$	50,598		—	$	50,598
	At December 31, 2013:
	Financial Assets:
	Derivative contracts for oil and natural gas		—	$	27,850		—	$	27,850
	Financial Liabilities:
	Derivative contracts for oil and natural gas		—	$	27,842		—	$	27,842
	The amounts above are presented on a gross basis; presentation on our consolidated balance sheets utilizes netting of assets and liabilities with the same counterparty where master netting agreements are in place. For additional information on derivative contracts, see Note 6.

Derivative_Financial_Instrumen

Derivative Financial Instruments	6 Months Ended
	Jun. 30, 2014
Derivative Financial Instruments [Abstract]	'
Derivative Financial Instruments	'
	6. DERIVATIVE FINANCIAL INSTRUMENTS
	We account for our derivative contracts under the provisions of ASC 815, “Derivatives and Hedging.” We have entered into forward-swap contracts and collar contracts to reduce our exposure to price risk in the spot market for oil and natural gas. We also have utilized financial basis swap contracts, which address the price differential between market-wide benchmark prices and other benchmark pricing referenced in certain of our crude oil and natural gas sales contracts. Substantially all of our hedging agreements are executed by affiliates of our lenders under the credit facility described in Note 8 below, and are collateralized by the security interests of the respective affiliated lenders in certain of our assets under the credit facility. The contracts settle monthly and are scheduled to coincide with either oil production equivalent to barrels (Bbl) per month or gas production equivalent to volumes in millions of British thermal units (MMbtu) per month. The contracts represent agreements between us and the counter-parties to exchange cash based on a designated price, or in the case of financial basis hedging contracts, based on a designated price differential between various benchmark prices. Cash settlement occurs monthly. No derivative contracts have been entered into for trading purposes, and we typically hold each instrument to maturity.
	We have not designated any of our derivative contracts as fair value or cash flow hedges; accordingly we use mark-to-market accounting, recognizing changes in the fair value of derivative contracts in the consolidated statement of operations at each reporting date.
	Derivative contracts are subject to master netting arrangements and are presented on a net basis in the consolidated balance sheets. This netting can cause derivative assets to be ultimately presented in a (liability) account on the consolidated balance sheets. Likewise, derivative (liabilities) could be presented in an asset account.
	The following table summarizes the fair value (see Note 5 for further discussion of fair value) and classification of our derivative instruments, none of which have been designated as hedging instruments under ASC 815.
	Fair Values of Derivative Contracts
								Net Fair
		Gross			Gross amounts			Value of Assets
	30-Jun-14	Fair Value			offset against assets			presented in
	Balance sheet location	of Assets			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
		(unaudited)
	Derivative financial instruments, current assets	$	7,444		$	-6,967		$	477
	Derivative financial instruments, long-term assets		12,295			-12,295			—
	Total	$	19,739		$	-19,262		$	477
								Net Fair
		Gross			Gross amounts			Value of Liabilities
	30-Jun-14	Fair Value			offset against liabilities			presented in
	Balance sheet location	of Liabilities			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
		(unaudited)
	Derivative financial instruments, current liabilities	$	22,934		$	-6,967		$	15,967
	Derivative financial instruments, long-term liabilities		27,664			-12,295			15,369
	Total	$	50,598		$	-19,262		$	31,336
								Net Fair
		Gross			Gross amounts			Value of Assets
	31-Dec-13	Fair Value			offset against assets			presented in
	Balance sheet location	of Assets			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
	Derivative financial instruments, current assets	$	13,218		$	-7,646		$	5,572
	Derivative financial instruments, long-term assets		14,632			-11,227			3,405
	Total	$	27,850		$	-18,873		$	8,977
								Net Fair
		Gross			Gross amounts			Value of Liabilities
	31-Dec-13	Fair Value			offset against liabilities			presented in
	Balance sheet location	of Liabilities			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
	Derivative financial instruments, current liabilities	$	12,129		$	-7,646		$	4,483
	Derivative financial instruments, long-term liabilities		15,713			-11,227			4,486
	Total	$	27,842		$	-18,873		$	8,969
	The following table summarizes the effect of our derivative instruments in the consolidated statements of operations:
	Derivatives not			Three Months Ended						Six Months Ended
	designated as hedging	Location of		June 30,						June 30,
	instruments under ASC 815	Gain (Loss)		2014			2013			2014		2013
				(dollars in thousands)
				(unaudited)
	Oil commodity contracts	Gain (loss) —
		oil and natural gas
		derivative contracts		$	-23,541		$	16,639		$	-28,510	$	12,210
	Natural gas commodity contracts	Gain (loss) —
		oil and natural gas
		derivative contracts			-1,188			9,508			-6,918		1,615
	Total gains (losses) from
	derivatives not designated as hedges			$	-24,729		$	26,147		$	-35,428	$	13,825
	Although our counterparties provide no collateral, the master derivative agreements with each counterparty effectively allow us, so long as we are not a defaulting party, after a default or the occurrence of a termination event, to set-off an unpaid hedging agreement receivable against the interest of the counterparty in any outstanding balance under the credit facility.
	If a counterparty were to default in payment of an obligation under the master derivative agreements, we could be exposed to commodity price fluctuations, and the protection intended by the hedge could be lost. The value of our derivative financial instruments would be impacted.
	We had the following open derivative contracts for natural gas at June  30, 2014 (unaudited):
	NATURAL GAS DERIVATIVE CONTRACTS
		Volume in		Weighted			Range
	Period and Type of Contract	MMBtu		Average			High			Low
	2014
	Price Swap Contracts	4,755,000		$	4.41		$	5.60		$	4.01
	Collar Contracts
Short Call Options	5,778,000			5.48			9.00			4.75
Long Put Options	1,670,000			4.86			6.00			4.25
Long Call Options	3,600,901			5.77			9.00			4.50
Short Put Options	5,227,600			3.58			4.00			3.00
2015
Price Swap Contracts	3,832,500			5.07			5.91			4.31
Collar Contracts
Short Call Options	7,750,000			4.59			5.75			4.51
Long Put Options	7,525,000			4.05			5.00			4.00
Short Put Options	9,102,500			3.32			4.45			3.25
2016
Price Swap Contracts	8,418,000			4.22			4.23			4.22
Collar Contracts
Short Call Options	455,000			7.50			7.50			7.50
Long Put Options	455,000			5.50			5.50			5.50
Short Put Options	455,000			4.00			4.00			4.00
2017
Collar Contracts
Short Call Options	6,570,000			5.00			5.00			4.98
Long Put Options	6,570,000			4.50			4.50			4.50
Short Put Options	6,570,000			4.00			4.00			4.00
2018
Collar Contracts
Short Call Options	5,475,000			5.50			5.53			5.48
Long Put Options	5,475,000			4.50			4.50			4.50
Short Put Options	5,475,000			4.00			4.00			4.00
We had the following open derivative contracts for crude oil at June  30, 2014 (unaudited):
OIL DERIVATIVE CONTRACTS
	Volume		Weighted			Range
Period and Type of Contract	in Bbls		Average			High			Low
2014
Price Swap Contracts	906,200		$	95.97		$	105.48		$	87.50
Collar Contracts
Short Call Options	511,520			104.00			111.30			97.00
Long Put Options	519,800			91.59			95.00			70.00
Long Call Options	621,920			101.83			110.00			90.00
Short Put Options	573,528			74.39			80.00			65.00
2015
Price Swap Contracts	1,404,500			94.36			99.30			86.45
Collar Contracts
Short Call Options	428,850			120.81			135.98			115.00
Long Put Options	1,231,850			87.15			95.00			85.00
Short Put Options	2,545,850			71.11			75.00			60.00
2016
Price Swap Contracts	366,000			93.00			94.92			85.35
Collar Contracts
Short Call Options	859,700			107.97			130.00			103.87
Long Put Options	859,700			85.98			95.00			80.00
Short Put Options	859,700			65.98			75.00			60.00
2017
Collar Contracts
Short Call Options	744,950			107.99			113.83			104.15
Long Put Options	744,950			83.26			90.00			80.00
Short Put Options	744,950			63.26			70.00			60.00
2018
Collar Contracts
Short Call Options	307,400			104.39			104.65			104.15
Long Put Options	307,400			80.00			80.00			80.00
Short Put Options	307,400			60.00			60.00			60.00
In those instances where contracts are identical as to time period, volume and strike price, and counterparty, but opposite as to direction (long and short), the volumes and average prices have been netted in the two tables above.  Prices stated in the table above for oil may settle against either the NYMEX or Brent ICE indices or may reflect a mix of positions settling on these two indices.

Asset_Retirement_Obligations

Asset Retirement Obligations	6 Months Ended
	Jun. 30, 2014
Asset Retirement Obligations [Abstract]	'
Asset Retirement Obligations	'
	7. ASSET RETIREMENT OBLIGATIONS
	A summary of the changes in asset retirement obligations is included in the table below (unaudited, dollars in thousands):
	Balance, beginning of year	$	56,023
	Liabilities incurred		408
	Liabilities settled		-1,617
	Liabilities transferred in sales of properties		-322
	Revisions to estimates		4,133
	Accretion expense		1,171
	Balance, June 30, 2014		59,796
	Less: Current portion		6,450
	Long term portion	$	53,346
	The total revisions include $2.8 million related to additions to property, plant and equipment.

LongTerm_Debt_And_Notes_Payabl

Long-Term Debt And Notes Payable To Founder	6 Months Ended
	Jun. 30, 2014
Long-Term Debt And Notes Payable To Founder [Abstract]	'
Long-Term Debt And Notes Payable To Founder	'
	8. LONG-TERM DEBT AND NOTES PAYABLE TO FOUNDER
	Long-term debt and notes payable to founder consists of the following:
		June 30,		December 31,
		2014		2013
		(dollars in thousands)
		(unaudited)
	Credit Facility	$	229,520	$	319,290
	Senior Notes		447,833		447,578
	Total long-term debt	$	677,353	$	766,868
	Notes payable to founder	$	23,931	$	23,331
	Credit Facility. On May 13, 2010, we entered into a Sixth Amended and Restated Credit Agreement (as amended, the “credit facility”). The credit facility matures on May 23, 2016 and is secured by substantially all of our oil and gas properties. The credit facility borrowing base is redetermined periodically and, as of June 30, 2014, the borrowing base under the facility was $285 million. The borrowing base was reduced from $385 million to $285 million on March 25, 2014 as a result of the sale of a portion of our Eagleville properties.  Subsequent to June 30, 2014, the borrowing base was increased to $350 million as of August 5, 2014. The credit facility bears interest at LIBOR plus applicable margins between 2.00% and 2.75% or a “Reference Rate,” which is based on the prime rate of Wells Fargo Bank, N. A., plus a margin ranging from 1.00% to 1.75%, depending on the utilization of our borrowing base. The rate was 2.75% as of June 30, 2014 and 2.75% as of December 31, 2013.
	The credit facility contains customary covenants including, among others, defined financial covenants, including minimum working capital levels (the ratio of current assets plus the unused borrowing base, to current liabilities, excluding assets and liabilities related to derivative contracts) of 1.0 to 1.0, minimum coverage of interest expenses of 3.0 to 1.0, and maximum leverage of 4.00 to 1.00.  The interest coverage and leverage ratios refer to the ratio of earnings before interest, taxes, depreciation, depletion, amortization, and exploration expense (“EBITDAX”, as defined more specifically in the credit agreement) to interest expense and to total debt (as defined), respectively. Financial ratios are calculated quarterly using EBITDAX for the most recent twelve months.  As of June  30, 2014, we were in compliance with all covenants.
	Senior Notes. We have $450 million in outstanding registered senior notes due October 15, 2018 that carry a stated interest rate of 9.625% and an effective rate of 9.783%.  Interest is payable semi-annually each April 15th and October 15th.  The senior notes are unsecured and are general obligations of the Company, and effectively rank junior to any of our existing or future secured indebtedness, which includes the credit facility. The senior notes are unconditionally guaranteed on a senior unsecured basis by each of our material subsidiaries. The balance is presented net of unamortized discount of $2.2 million and $2.4 million at June 30, 2014 and December 31, 2013, respectively.
	The senior notes contain an optional redemption provision beginning October 15, 2014 allowing us to retire the principal outstanding, in whole or in part, at 104.813%.   Additional optional redemption provisions allow for retirement at 102.406% and 100.0% beginning on each of October 15, 2015 and 2016, respectively.  Prior to October 15, 2014, we may redeem the senior notes in whole or in part at a price equal to 100 percent of the principal amount plus a specified make-whole premium and accrued and unpaid interest to the applicable redemption date.
	Notes Payable to Founder. We have notes payable to our founder that bear simple interest at 10% with a balance of $23.9 million and $23.3 million at June 30, 2014 and December 31, 2013, respectively.  The maturity date was extended from December 31, 2018 to December 31, 2021 on March 25, 2014.  Interest and principal are payable at maturity. The notes are convertible into shares of our Class B partner, Alta Mesa Investment Holdings, Inc., common stock upon certain conditions in the event of an initial public offering.
	These founder notes are unsecured and subordinate to all debt. In connection with the March 25, 2014 recapitalization of our Class B partner described in Note 12, the founder notes were amended and restated to subordinate them to the PIK notes of our Class B partner.  The founder notes were also subordinated to the rights of the holders of Class B units to receive distributions under our amended partnership agreement and subordinated to the rights of the holders of Series B Preferred Stock to receive payments.
	Interest on the notes payable to our founder amounted to $0.6 million and $0.6 million for the six months ended June 30, 2014 and 2013, respectively, and $0.3 million and $0.3 million for the three months ended June 30, 2014 and 2013, respectively. Such amounts have been added to the balance of the founder notes.

Accounts_Payable_And_Accrued_L

Accounts Payable And Accrued Liabilities	6 Months Ended
	Jun. 30, 2014
Accounts Payable And Accrued Liabilities [Abstract]	'
Accounts Payable And Accrued Liabilities	'
	9. ACCOUNTS PAYABLE AND ACCRUED LIABILITIES
	The following provides the detail of accounts payable and accrued liabilities:
		June 30,		December 31,
		2014		2013
		(dollars in thousands)
		(unaudited)
	Capital expenditures	$	28,052	$	18,629
	Revenues and royalties payable		7,262		9,699
	Operating expenses/taxes		20,663		17,071
	Interest		9,816		9,146
	Compensation		9,019		8,862
	Other		9,562		2,711
	Total accrued liabilities		84,374		66,118
	Accounts payable		25,146		29,977
	Accounts payable and accrued liabilities	$	109,520	$	96,095

Commitments_And_Contingencies

Commitments And Contingencies	6 Months Ended
	Jun. 30, 2014
Commitments And Contingencies [Abstract]	'
Commitments And Contingencies	'
	10. COMMITMENTS AND CONTINGENCIES
	Contingencies
	Board of Commissioners of the Southeast Louisiana Flood Protection Authority – East:    On July 24, 2013, the Board of Commissioners of the Southeast Louisiana Flood Protection Authority – East sued us and approximately 100 other energy companies for long-term damage to the wetlands in southeast Louisiana.  Case No. 2013-6911 was filed in state court and subsequently remanded to federal court.  The plaintiff seeks damages and injunctive relief in the form of abatement and restoration of wetlands, alleging that the activities of the oil and gas industry over the past century have contributed significantly to the degradation of the wetlands that protect the populated areas in and around New Orleans from storm surge and other extreme weather effects.  The plaintiff alleges damages from increased costs of providing man-made storm protection structures, and emphasizes the destructive effect of canals built by the oil and gas industry.  Legal arguments include breach of the restoration and maintenance clauses of contracts with the State of Louisiana for drilling, dredging, and right-of-way agreements for pipelines.  Other legal arguments include negligence, strict liability, natural servitude of drain, public nuisance and private nuisance.   Our wholly-owned subsidiary The Meridian Resource & Exploration LLC is named as a defendant with 32 wells, two dredging permits and four right of way agreements in the relevant area.  Almost all of these wells are inactive.  In June 2014, Act 544 of the Louisiana Legislature was enacted, stating that the plaintiff does not have the authority to bring this suit.  However, the constitutionality of Act 544 may be litigated, and this development does not end the litigation to which we are a party.
	The overall exposure related to this lawsuit is not currently determinable.  While an adverse judgment against us might be possible, we intend to vigorously defend the case.  We have not provided any amount for this matter in our consolidated financial statements at June 30, 2014.
	Environmental claims: Various landowners have sued the Company and/or our wholly owned subsidiaries, in lawsuits concerning several fields in which we have or historically had operations in Louisiana.  The lawsuits seek injunctive relief and other relief, including unspecified amounts in both actual and punitive damages for alleged breaches of mineral leases and alleged failure to restore the plaintiffs’ lands from alleged contamination and otherwise from our oil and natural gas operations. We are unable to express an opinion with respect to the likelihood of an unfavorable outcome of the various environmental claims or to estimate the amount or range of potential loss should the outcome be unfavorable. Therefore, we have not provided any material amounts for these claims in our consolidated financial statements at June 30, 2014, other than the balance for Florida, described below.
	Due to the nature of our business, some contamination of the real estate property owned or leased by us is possible. Environmental site assessments of the property would be necessary to adequately determine remediation costs, if any.  Management has established a liability for soil contamination in Florida of $1.1 million and $1.1 million at June  30, 2014 and December 31, 2013, respectively, based on our undiscounted engineering estimates. The obligations are included in other long-term liabilities in the accompanying consolidated balance sheets.
	Title/lease disputes: Title and lease disputes may arise in the normal course of our operations. These disputes are usually small but could result in an increase or decrease in reserves and/or other forms of settlement, such as cash, once a final resolution to the title dispute is made.
	Other contingencies: We are subject to legal proceedings, claims and liabilities arising in the ordinary course of business for which the outcome cannot be reasonably estimated; however, in the opinion of management, such litigation and claims will be resolved without material adverse effect on our financial position, results of operations or cash flows. Accruals for losses associated with litigation are made when losses are deemed probable and can be reasonably estimated.

Significant_Risks_And_Uncertai

Significant Risks And Uncertainties	6 Months Ended
	Jun. 30, 2014
Significant Risks And Uncertainties [Abstract]	'
Significant Risks And Uncertainties	'
	11. SIGNIFICANT RISKS AND UNCERTAINTIES
	Our business makes us vulnerable to changes in wellhead prices of crude oil and natural gas. Such prices have been volatile in the past and can be expected to be volatile in the future. By definition, proved reserves are based on analysis of current oil and natural gas prices.  Price declines reduce the estimated value of proved reserves and may increase annual amortization expense (which is based on proved reserves).  Price declines may also result in impairments, or non-cash write-downs, of the value of our oil and natural gas properties.  We mitigate a portion of this vulnerability by entering into oil and natural gas price derivative contracts.  See Note 6.

Partners_Capital_Deficit

Partners' Capital (Deficit)	6 Months Ended
	Jun. 30, 2014
Partners' Capital (Deficit) [Abstract]	'
Partners' Capital (Deficit)	'
	12. PARTNERS’ CAPITAL (DEFICIT)
	Our business and affairs are managed by Alta Mesa Holdings GP, LLC, our general partner (“General Partner”) as provided in the Alta Mesa Holdings, LP partnership agreement.  Our partnership agreement provides for two classes of limited partners.  Class A partners include our founder and other parties.  Our Class B partner is Alta Mesa Investment Holdings, Inc. (“AMIH.”)  Prior to March 25, 2014, AMIH was an affiliate of Denham Capital Management LP, a private equity firm focused on energy and commodities.
	On March 25, 2014, AMIH completed a $350 million recapitalization with an investment from Highbridge Principal Strategies LLC (“Highbridge”).  Proceeds from the investment were used in part to purchase the investment of Denham Capital Management LP in AMIH. Highbridge received convertible PIK preferred stock in AMIH and senior PIK notes from AMIH.  We expanded our Board of Directors to include one member nominated by Highbridge and one new employee member, our Chief Financial Officer, Michael A. McCabe.  AMIH remains our sole Class B partner.
	In connection with the recapitalization, our partnership agreement was amended and restated to provide, among other things, that all distributions under the partnership agreement shall first be made to holders of Class B Units, until all principal and interest has been extinguished under the senior PIK notes issued to Highbridge.  After such extinguishment of the senior PIK notes, distributions shall then be made to holders of Class A and Class B Units pursuant to the distribution formulas set forth in the amended partnership agreement.

Subsidiary_Guarantors

Subsidiary Guarantors	6 Months Ended
	Jun. 30, 2014
Subsidiary Guarantors [Abstract]	'
Subsidiary Guarantors	'
	13. SUBSIDIARY GUARANTORS
	All of our material wholly-owned subsidiaries are guarantors under the terms of both our senior notes and our credit facility. Our consolidated financial statements reflect the combined financial position of these subsidiary guarantors. Our parent company, Alta Mesa Holdings, LP, has no independent operations, assets, or liabilities. The guarantees are full and unconditional and joint and several. Those subsidiaries which are not wholly owned and are not guarantors are minor. There are no restrictions on dividends, distributions, loans, or other transfers of funds from the subsidiary guarantors to our parent company.

Summary_Of_Significant_Account

Summary Of Significant Accounting Policies (Policy)	6 Months Ended
	Jun. 30, 2014
Summary Of Significant Accounting Policies [Abstract]	'
Use Of Estimates	'
	Use of Estimates:  The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period.
	Reserve estimates significantly impact depreciation, depletion and amortization expense and potential impairments of oil and natural gas properties and are subject to change based on changes in oil and natural gas prices and trends and changes in estimated reserve quantities. We analyze estimates, including those related to oil and natural gas reserves, oil and natural gas revenues, the value of oil and natural gas properties, bad debts, asset retirement obligations, derivative contracts, income taxes and contingencies and litigation. We base our estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from these estimates.
Reclassifications	'
	Reclassifications:   Certain amounts in the 2013 consolidated financial statements have been reclassified to conform to the 2014 presentation. The reclassifications had no impact on net income (loss) or partners’ capital (deficit).
Accounts Receivable	'
	Accounts Receivable, net:  Our receivables arise from the sale of oil and natural gas to third parties and joint interest owner receivables for properties in which we serve as the operator. This concentration of customers may impact our overall credit risk, either positively or negatively, in that these entities may be similarly affected by changes in economic or other conditions affecting the oil and gas industry. Accounts receivable are generally not collateralized. Accounts receivable are shown net of an allowance for doubtful accounts of $1.3 million and $1.4 million at June 30, 2014 and December 31, 2013, respectively.
Deferred Financing Costs	'
	Deferred Financing Costs:  Deferred financing costs and the amount of discount at which notes payable have been issued (debt discount) are amortized using the straight-line method, which approximates the interest method, over the term of the related debt. For the three month periods ended June 30, 2014 and 2013, amortization of deferred financing costs included in interest expense amounted to $0.7 million and $0.7 million, respectively. For the six month periods ended June 30, 2014 and 2013, amortization of deferred financing costs included in interest expense amounted to $1.4 million and $1.4 million, respectively. Deferred financing costs are listed among our long-term assets, net of accumulated amortization of $14.2 million and $12.8 million at June 30, 2014 and December 31, 2013, respectively.
Property And Equipment	'
	Property and Equipment:  Oil and natural gas producing activities are accounted for using the successful efforts method of accounting. Under the successful efforts method, lease acquisition costs and all development costs, including unsuccessful development wells, are capitalized.
	Unproved Properties — Acquisition costs associated with the acquisition of leases are recorded as unproved leasehold costs and capitalized as incurred. These consist of costs incurred in obtaining a mineral interest or right in a property such as a lease, in addition to options to lease, broker fees, recording fees and other similar costs related to activities in acquiring properties. Unproved properties are classified as unproved until proved reserves are discovered, at which time related costs are transferred to proved oil and natural gas properties.
	Exploration Expense — Exploration expenses, other than exploration drilling costs, are charged to expense as incurred. These costs include seismic expenditures and other geological and geophysical costs, expired leases, gain or loss on settlement of asset retirement obligations and lease rentals. The costs of drilling exploratory wells and exploratory-type stratigraphic wells are initially capitalized pending determination of whether the well has discovered proved commercial reserves. If the exploratory well is determined to be unsuccessful, the cost of the well is transferred to expense. Exploratory well drilling costs may continue to be capitalized if the reserve quantity is sufficient to justify completion as a producing well and sufficient progress in assessing the reserves and the economic and operating viability of the project is being made. Assessments of such capitalized costs are made quarterly.
	Proved Oil and Natural Gas Properties — Costs incurred to obtain access to proved reserves and to provide facilities for extracting, treating, gathering, and storing oil and natural gas are capitalized. All costs incurred to drill and equip successful exploratory wells, development wells, development-type stratigraphic test wells, and service wells, including unsuccessful development wells, are capitalized.
	Impairment — The capitalized costs of proved oil and natural gas properties are reviewed quarterly for impairment following the guidance provided in Accounting Standards Codification (“ASC”) 360-10-35, “Property, Plant and Equipment, Subsequent Measurement,” or whenever events or changes in circumstances indicate that the carrying amount of a long-lived asset or asset group exceeds its fair market value and is not recoverable. The determination of recoverability is based on comparing the estimated undiscounted future net cash flows at a producing field level to the carrying value of the assets. If the future undiscounted cash flows, based on estimates of anticipated production from proved reserves and future crude oil and natural gas prices and operating costs, are lower than the carrying cost, the carrying cost of the asset or group of assets is reduced to fair value. For our proved oil and natural gas properties, we estimate fair value by discounting the projected future cash flows at an appropriate risk-adjusted discount rate. Unproved leasehold costs are assessed quarterly to determine whether they have been impaired. Individually significant properties are assessed for impairment on a property-by-property basis, while individually insignificant unproved leasehold costs may be assessed in the aggregate. If unproved leasehold costs are found to be impaired, an impairment allowance is provided and a loss is recognized in the consolidated statement of operations.
	Depreciation, Depletion, and Amortization — Depreciation, depletion, and amortization (“DD&A”) of capitalized costs of proved oil and natural gas properties is computed using the unit-of-production method based upon estimated proved reserves. Assets are grouped for DD&A on the basis of reasonable aggregation of properties with a common geological structural feature or stratigraphic condition, such as a reservoir or field. The reserve base used to calculate DD&A for leasehold acquisition costs and the cost to acquire proved properties is the sum of proved developed reserves and proved undeveloped reserves. The reserve base used to calculate DD&A for lease and well equipment costs, which include development costs and successful exploration drilling costs, includes only proved developed reserves.
Derivative Financial Instruments	'
	We have not designated any of our derivative contracts as fair value or cash flow hedges; accordingly we use mark-to-market accounting, recognizing changes in the fair value of derivative contracts in the consolidated statement of operations at each reporting date.
	Derivative contracts are subject to master netting arrangements and are presented on a net basis in the consolidated balance sheets. This netting can cause derivative assets to be ultimately presented in a (liability) account on the consolidated balance sheets. Likewise, derivative (liabilities) could be presented in an asset account.
Fair Value Of Financial Instruments	'
	Fair Value of Financial Instruments:  The fair value of cash, accounts receivable, other current assets, and current liabilities approximate book value due to their short-term nature. The estimate of fair value of long-term debt under our senior secured revolving credit facility is not considered to be materially different from carrying value due to market rates of interest. The fair value of the notes payable to our founder is not practicable to determine. We have estimated the fair value of our $450 million senior notes payable at $473.6 million at June 30, 2014. See Note 5 for further information on fair values of financial instruments. See Note 8 for information on long-term debt.
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	In April 2014, the Financial Accounting Standards Board issued Accounting Standards Update (“ASU”) 2014-08, “Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity.”  ASU 2014-08 narrows the definition of “discontinued operations” to dispositions that represent a strategic shift that has or will have a significant impact on the entity’s operations and financial results.  The ASU requires additional disclosures regarding assets and liabilities held for sale, and income and losses, including gain or loss on sale, and cash flows from discontinued operations.  In addition, the ASU requires disclosures for disposals of individually significant components of the business which do not qualify as discontinued operations, including general information about the disposition and disclosure of the pretax profit or loss from the component for the period of disposal and all comparable historic periods presented.  ASU 2014-08 is effective for all fiscal years beginning after December 15, 2014, and can be adopted early for certain asset dispositions and reclassifications of assets from “held and used” to “held for sale.”
	In May 2014, the FASB issued Accounting Standards Update 2014-09, Revenue from Contracts with Customers (Topic 606).  The update provides guidance concerning the recognition and measurement of revenue from contracts with customers.  Its objective is to increase the usefulness of information in the financial statements regarding the nature, timing and uncertainty of revenues.  The update is effective for the Company beginning in calendar year 2017.  We are evaluating the impact this standard will have on our consolidated financial statements and related disclosures.

Fair_Value_Disclosures_Policy

Fair Value Disclosures (Policy)	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements And Disclosures	'
	We follow the guidance of ASC 820, “Fair Value Measurements and Disclosures,” in the estimation of fair values. ASC 820 provides a hierarchy of fair value measurements, based on the inputs to the fair value estimation process. It requires disclosure of fair values classified according to defined “levels,” which are based on the reliability of the evidence used to determine fair value, with Level 1 being the most reliable and Level 3 the least reliable. Level 1 evidence consists of observable inputs, such as quoted prices in an active market. Level 2 inputs typically correlate the fair value of the asset or liability to a similar, but not identical item which is actively traded. Level 3 inputs include at least some unobservable inputs, such as valuation models developed using the best information available in the circumstances.
	We utilize the modified Black-Scholes and the Turnbull Wakeman option pricing models to estimate the fair values of oil and natural gas derivative contracts. Inputs to these models include observable inputs from the New York Mercantile Exchange (“NYMEX”) for futures contracts, and inputs derived from NYMEX observable inputs, such as implied volatility of oil and natural gas prices. We have classified the fair values of all our oil and natural gas derivative contracts as Level 2.

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Policy)	6 Months Ended
	Jun. 30, 2014
Derivatives And Hedging	'
	We have not designated any of our derivative contracts as fair value or cash flow hedges; accordingly we use mark-to-market accounting, recognizing changes in the fair value of derivative contracts in the consolidated statement of operations at each reporting date.
	Derivative contracts are subject to master netting arrangements and are presented on a net basis in the consolidated balance sheets. This netting can cause derivative assets to be ultimately presented in a (liability) account on the consolidated balance sheets. Likewise, derivative (liabilities) could be presented in an asset account.
Energy Related Derivative [Member]	'
Derivatives, Use of Derivatives	'We account for our derivative contracts under the provisions of ASC 815, "Derivatives and Hedging." We have entered into forward-swap contracts and collar contracts to reduce our exposure to price risk in the spot market for oil and natural gas. We also have utilized financial basis swap contracts, which address the price differential between market-wide benchmark prices and other benchmark pricing referenced in certain of our crude oil and natural gas sales contracts. Substantially all of our hedging agreements are executed by affiliates of our lenders under the credit facility described in Note 8 below, and are collateralized by the security interests of the respective affiliated lenders in certain of our assets under the credit facility. The contracts settle monthly and are scheduled to coincide with either oil production equivalent to barrels (Bbl) per month or gas production equivalent to volumes in millions of British thermal units (MMbtu) per month. The contracts represent agreements between us and the counter-parties to exchange cash based on a designated price, or in the case of financial basis hedging contracts, based on a designated price differential between various benchmark prices. Cash settlement occurs monthly. No derivative contracts have been entered into for trading purposes, and we typically hold each instrument to maturity.

Significant_Acquisitions_And_D1

Significant Acquisitions And Divestitures (Tables) (Stone [Member])	6 Months Ended
	Jun. 30, 2014
Stone [Member]	'
Summary Of Consideration Paid And The Preliminary Allocation Of Purchase Prices	'
		October 1,
		2013
		(dollars in thousands)
		(unaudited)
	Summary of Consideration
	Cash	$	41,841
	Fair value of asset retirement obligations assumed		5,311
	Total	$	47,152
	Summary of Purchase Price Allocation
	Proved oil and natural gas properties	$	30,279
	Unproved oil and natural gas properties		16,873
	Total	$	47,152
Summary Of Pro Forma Information	'
		Total
		Revenue		Income
		(dollars in thousands)
		(unaudited)
	Pro forma results for the six months ended June 30, 2013	$	213,283	$	8,625

Property_And_Equipment_Tables

Property And Equipment (Tables)	6 Months Ended
	Jun. 30, 2014
Property And Equipment [Abstract]	'
Property And Equipment	'
		June 30,		December 31,
		2014		2013
		(dollars in thousands)
		(unaudited)
	OIL AND NATURAL GAS PROPERTIES
	Unproved properties	$	77,094	$	86,721
	Accumulated impairment		-5,191		-7,356
	Unproved properties, net		71,903		79,365
	Proved oil and natural gas properties		1,414,221		1,405,658
	Accumulated depreciation, depletion, amortization and impairment		-816,944		-793,253
	Proved oil and natural gas properties, net		597,277		612,405
	TOTAL OIL AND NATURAL GAS PROPERTIES, net		669,180		691,770
	LAND		1,918		1,418
	OTHER PROPERTY AND EQUIPMENT
	Office furniture and equipment, vehicles		15,012		13,802
	Accumulated depreciation		-7,301		-6,120
	OTHER PROPERTY AND EQUIPMENT, net		7,711		7,682
	TOTAL PROPERTY AND EQUIPMENT, net	$	678,809	$	700,870

Fair_Value_Disclosures_Tables

Fair Value Disclosures (Tables)	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Measurement Of Fair Value Of Assets And Liabilities On Recurring Basis	'
		Level 1		Level 2		Level 3		Total
			(dollars in thousands)
	At June 30, 2014 (unaudited):
	Financial Assets:
	Derivative contracts for oil and natural gas		—	$	19,739		—	$	19,739
	Financial Liabilities:
	Derivative contracts for oil and natural gas		—	$	50,598		—	$	50,598
	At December 31, 2013:
	Financial Assets:
	Derivative contracts for oil and natural gas		—	$	27,850		—	$	27,850
	Financial Liabilities:
	Derivative contracts for oil and natural gas		—	$	27,842		—	$	27,842

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2014
Derivative [Line Items]	'
Fair Values Of Derivative Contracts	'
	Fair Values of Derivative Contracts
								Net Fair
		Gross			Gross amounts			Value of Assets
	30-Jun-14	Fair Value			offset against assets			presented in
	Balance sheet location	of Assets			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
		(unaudited)
	Derivative financial instruments, current assets	$	7,444		$	-6,967		$	477
	Derivative financial instruments, long-term assets		12,295			-12,295			—
	Total	$	19,739		$	-19,262		$	477
								Net Fair
		Gross			Gross amounts			Value of Liabilities
	30-Jun-14	Fair Value			offset against liabilities			presented in
	Balance sheet location	of Liabilities			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
		(unaudited)
	Derivative financial instruments, current liabilities	$	22,934		$	-6,967		$	15,967
	Derivative financial instruments, long-term liabilities		27,664			-12,295			15,369
	Total	$	50,598		$	-19,262		$	31,336
								Net Fair
		Gross			Gross amounts			Value of Assets
	31-Dec-13	Fair Value			offset against assets			presented in
	Balance sheet location	of Assets			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
	Derivative financial instruments, current assets	$	13,218		$	-7,646		$	5,572
	Derivative financial instruments, long-term assets		14,632			-11,227			3,405
	Total	$	27,850		$	-18,873		$	8,977
								Net Fair
		Gross			Gross amounts			Value of Liabilities
	31-Dec-13	Fair Value			offset against liabilities			presented in
	Balance sheet location	of Liabilities			in the Balance Sheet			the Balance Sheet
		(dollars in thousands)
	Derivative financial instruments, current liabilities	$	12,129		$	-7,646		$	4,483
	Derivative financial instruments, long-term liabilities		15,713			-11,227			4,486
	Total	$	27,842		$	-18,873		$	8,969
Effect Of Derivative Instruments In The Consolidated Statements Of Operations	'
	Derivatives not			Three Months Ended						Six Months Ended
	designated as hedging	Location of		June 30,						June 30,
	instruments under ASC 815	Gain (Loss)		2014			2013			2014		2013
				(dollars in thousands)
				(unaudited)
	Oil commodity contracts	Gain (loss) —
		oil and natural gas
		derivative contracts		$	-23,541		$	16,639		$	-28,510	$	12,210
	Natural gas commodity contracts	Gain (loss) —
		oil and natural gas
		derivative contracts			-1,188			9,508			-6,918		1,615
	Total gains (losses) from
	derivatives not designated as hedges			$	-24,729		$	26,147		$	-35,428	$	13,825
Natural Gas [Member]	'
Derivative [Line Items]	'
Open Derivative Contracts	'
		Volume in		Weighted			Range
	Period and Type of Contract	MMBtu		Average			High			Low
	2014
	Price Swap Contracts	4,755,000		$	4.41		$	5.60		$	4.01
	Collar Contracts
	Short Call Options	5,778,000			5.48			9.00			4.75
	Long Put Options	1,670,000			4.86			6.00			4.25
	Long Call Options	3,600,901			5.77			9.00			4.50
	Short Put Options	5,227,600			3.58			4.00			3.00
	2015
	Price Swap Contracts	3,832,500			5.07			5.91			4.31
	Collar Contracts
	Short Call Options	7,750,000			4.59			5.75			4.51
	Long Put Options	7,525,000			4.05			5.00			4.00
	Short Put Options	9,102,500			3.32			4.45			3.25
	2016
	Price Swap Contracts	8,418,000			4.22			4.23			4.22
	Collar Contracts
	Short Call Options	455,000			7.50			7.50			7.50
	Long Put Options	455,000			5.50			5.50			5.50
	Short Put Options	455,000			4.00			4.00			4.00
	2017
	Collar Contracts
	Short Call Options	6,570,000			5.00			5.00			4.98
	Long Put Options	6,570,000			4.50			4.50			4.50
	Short Put Options	6,570,000			4.00			4.00			4.00
	2018
	Collar Contracts
	Short Call Options	5,475,000			5.50			5.53			5.48
	Long Put Options	5,475,000			4.50			4.50			4.50
	Short Put Options	5,475,000			4.00			4.00			4.00
Oil [Member]	'
Derivative [Line Items]	'
Open Derivative Contracts	'
		Volume		Weighted			Range
	Period and Type of Contract	in Bbls		Average			High			Low
	2014
	Price Swap Contracts	906,200		$	95.97		$	105.48		$	87.50
	Collar Contracts
	Short Call Options	511,520			104.00			111.30			97.00
	Long Put Options	519,800			91.59			95.00			70.00
	Long Call Options	621,920			101.83			110.00			90.00
	Short Put Options	573,528			74.39			80.00			65.00
	2015
	Price Swap Contracts	1,404,500			94.36			99.30			86.45
	Collar Contracts
	Short Call Options	428,850			120.81			135.98			115.00
	Long Put Options	1,231,850			87.15			95.00			85.00
	Short Put Options	2,545,850			71.11			75.00			60.00
	2016
	Price Swap Contracts	366,000			93.00			94.92			85.35
	Collar Contracts
	Short Call Options	859,700			107.97			130.00			103.87
	Long Put Options	859,700			85.98			95.00			80.00
	Short Put Options	859,700			65.98			75.00			60.00
	2017
	Collar Contracts
	Short Call Options	744,950			107.99			113.83			104.15
	Long Put Options	744,950			83.26			90.00			80.00
	Short Put Options	744,950			63.26			70.00			60.00
	2018
	Collar Contracts
	Short Call Options	307,400			104.39			104.65			104.15
	Long Put Options	307,400			80.00			80.00			80.00
	Short Put Options	307,400			60.00			60.00			60.00

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	6 Months Ended
	Jun. 30, 2014
Asset Retirement Obligations [Abstract]	'
Summary Of Changes In Asset Retirement Obligations	'
	Balance, beginning of year	$	56,023
	Liabilities incurred		408
	Liabilities settled		-1,617
	Liabilities transferred in sales of properties		-322
	Revisions to estimates		4,133
	Accretion expense		1,171
	Balance, June 30, 2014		59,796
	Less: Current portion		6,450
	Long term portion	$	53,346

LongTerm_Debt_And_Notes_Payabl1

Long-Term Debt And Notes Payable To Founder (Tables)	6 Months Ended
	Jun. 30, 2014
Long-Term Debt And Notes Payable To Founder [Abstract]	'
Long-Term Debt	'
		June 30,		December 31,
		2014		2013
		(dollars in thousands)
		(unaudited)
	Credit Facility	$	229,520	$	319,290
	Senior Notes		447,833		447,578
	Total long-term debt	$	677,353	$	766,868
	Notes payable to founder	$	23,931	$	23,331

Accounts_Payable_And_Accrued_L1

Accounts Payable And Accrued Liabilities (Tables)	6 Months Ended
	Jun. 30, 2014
Accounts Payable And Accrued Liabilities [Abstract]	'
Detail Of Accounts Payable And Accrued Liabilities	'
		June 30,		December 31,
		2014		2013
		(dollars in thousands)
		(unaudited)
	Capital expenditures	$	28,052	$	18,629
	Revenues and royalties payable		7,262		9,699
	Operating expenses/taxes		20,663		17,071
	Interest		9,816		9,146
	Compensation		9,019		8,862
	Other		9,562		2,711
	Total accrued liabilities		84,374		66,118
	Accounts payable		25,146		29,977
	Accounts payable and accrued liabilities	$	109,520	$	96,095

Summary_Of_Significant_Account1

Summary Of Significant Accounting Policies (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Summary Of Significant Accounting Policies [Abstract]	'	'	'	'	'
Allowance for Doubtful Accounts Receivable, Current	$1,300,000	'	$1,300,000	'	$1,400,000
Amortization of loan costs	700,000	700,000	1,433,000	1,409,000	'
Accumulated amortization, deferred financing costs	14,200,000	'	14,200,000	'	12,800,000
Face value of senior notes issued	450,000,000	'	450,000,000	'	'
Fair value of senior notes payable	$473,600,000	'	$473,600,000	'	'

Significant_Acquisitions_And_D2

Significant Acquisitions And Divestitures (Narrative) (Details) (USD $)

0 Months Ended

6 Months Ended

0 Months Ended

3 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

Oct. 01, 2013

Jun. 30, 2014

Oct. 01, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Oct. 02, 2013

Jun. 30, 2014

Mar. 31, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Stone [Member]

Stone [Member]

Stone [Member]

Hilltop Divestiture [Member]

Hilltop Divestiture [Member]

Hilltop Divestiture [Member]

Hilltop Divestiture [Member]

Hilltop Divestiture [Member]

Eagleville Divestiture [Member]

Eagleville Divestiture [Member]

Eagleville Divestiture [Member]

Eagleville Divestiture [Member]

Eagleville Divestiture [Member]

Eagleville Divestiture [Member]

Barrels of Oil Equivalent [Member]

Natural Gas in MMcf [Member]

Barrels of Oil Equivalent [Member]

bbl

MMcf

bbl

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Acquisition, Date of Acquisition Agreement

1-Oct-13

'

'

'

'

'

'

'

'

'

'

'

'

'

Initial Cash Payment for Busines Acquisition

$45,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Payments to Acquire Businesses, Gross

'

41,841,000

'

'

'

'

'

'

'

'

'

'

'

'

Proved Reserves Acquired

'

'

1,800,000

'

'

'

'

'

'

'

'

'

'

'

Acquisition effective date

1-Jul-13

'

'

'

'

'

'

'

'

'

'

'

'

'

Date of acquisition or sale of properties

'

'

'

2-Oct-13

'

'

'

'

25-Mar-14

'

'

'

'

'

Estimated net proved reserves associated with sold properties

'

'

'

'

'

'

'

11,200

'

'

'

'

'

7,700,000

Initial Cash Price For Properties Sold

'

'

'

'

'

'

'

'

'

'

'

173,000,000

'

'

Cash Purchase Price For Properties Sold

'

'

'

'

'

19,000,000

'

'

'

'

'

168,000,000

'

'

Percentage Of Original Working Interest Net Profits Interest In Wells Is Retained On, Year One

'

'

'

'

'

'

'

'

50.00%

'

'

50.00%

'

'

Percentage Of Original Working Interest Net Profits Interest In Wells Is Retained On, Year Two

'

'

'

'

'

'

'

'

30.00%

'

'

30.00%

'

'

Percentage Of Original Working Interest Net Profits Interest In Wells Is Retained On, Year Three

'

'

'

'

'

'

'

'

15.00%

'

'

15.00%

'

'

Percentage Of Original Working Interest Net Profits Interest In Wells Is Retained On, Year Four

'

'

'

'

'

'

'

'

0.00%

'

'

0.00%

'

'

Percentage Of Undivided Interest In Mineral Leases And Interests Included In Sale

'

'

'

'

'

'

'

'

30.00%

'

'

30.00%

'

'

Percentage Of Working Interest In All Wells In Progress Included In Sale

'

'

'

'

'

'

'

'

30.00%

'

'

30.00%

'

'

Gain on sale of oil and gas properties

'

'

'

'

'

0

'

'

'

'

'

68,700,000

'

'

Operating income from sold oil and gas properties

'

'

'

'

$200,000

'

$100,000

'

'

$6,600,000

$8,600,000

'

$16,400,000

'

Significant_Acquisitions_And_D3

Significant Acquisitions And Divestitures (Summary Of Consideration Paid And The Preliminary Allocation Of Purchase Prices) (Details) (Stone [Member], USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014
Stone [Member]	'
Business Acquisition [Line Items]	'
Cash	$41,841
Fair value of asset retirement obligations assumed	5,311
Total	47,152
Proved oil and natural gas properties	30,279
Unproved oil and natural gas properties	16,873
Total	$47,152

Significant_Acquisitions_And_D4

Significant Acquisitions And Divestitures (Summary Of Pro Forma Information) (Details) (Stone [Member], Pro Forma [Member], USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2013
Stone [Member] | Pro Forma [Member]	'
Business Acquisition [Line Items]	'
Pro Forma Revenue	$213,283
Pro Forma Income (Loss)	$8,625

Property_And_Equipment_Propert

Property And Equipment (Property And Equipment) (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property And Equipment [Abstract]	'	'
Unproved properties	$77,094	$86,721
Accumulated impairment	-5,191	-7,356
Unproved properties, net	71,903	79,365
Proved oil and natural gas properties	1,414,221	1,405,658
Accumulated depreciation, depletion, amortization and impairment	-816,944	-793,253
Proved oil and natural gas properties, net	597,277	612,405
TOTAL OIL AND NATURAL GAS PROPERTIES, net	669,180	691,770
LAND	1,918	1,418
Office furniture and equipment, vehicles	15,012	13,802
Accumulated depreciation	-7,301	-6,120
OTHER PROPERTY AND EQUIPMENT, net	7,711	7,682
TOTAL PROPERTY AND EQUIPMENT, NET	$678,809	$700,870

Property_And_Equipment_Capital

Property And Equipment (Capitalized Exploratory Well Costs) (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014
Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves	'
Capitalized Exploratory Well Costs, Beginning Balance	$18.40
Capitalized exploratory well costs charged to expense	13.5
Capitalized Exploratory Well Costs, Ending Balance	6.5
Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year	$3.30

Fair_Value_Disclosures_Narrati

Fair Value Disclosures (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Fair Value Disclosures [Abstract]	'	'	'	'
Carrying value of oil and gas properties	$59,100,000	$35,400,000	$60,300,000	$46,500,000
Written down fair value of oil and gas properties	40,800,000	16,200,000	41,100,000	20,000,000
Impairment charges to oil and gas properties	18,300,000	19,191,000	19,202,000	26,546,000
Asset retirement obligation measured at fair value	'	'	$400,000	$400,000

Fair_Value_Disclosures_Measure

Fair Value Disclosures (Measurement Of Fair Value Of Assets And Liabilities On Recurring Basis) (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financial Assets:	'	'
Derivative contracts for oil and natural gas, gross	$19,739	$27,850
Financial Liabilities:	'	'
Derivative contracts for oil and natural gas, gross	50,598	27,842
Level 1 [Member]	'	'
Financial Assets:	'	'
Derivative contracts for oil and natural gas, gross	'	'
Financial Liabilities:	'	'
Derivative contracts for oil and natural gas, gross	'	'
Level 2 [Member]	'	'
Financial Assets:	'	'
Derivative contracts for oil and natural gas, gross	19,739	27,850
Financial Liabilities:	'	'
Derivative contracts for oil and natural gas, gross	50,598	27,842
Level 3 [Member]	'	'
Financial Assets:	'	'
Derivative contracts for oil and natural gas, gross	'	'
Financial Liabilities:	'	'
Derivative contracts for oil and natural gas, gross	'	'

Derivative_Financial_Instrumen3

Derivative Financial Instruments (Fair Values Of Derivative Contracts) (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Derivatives, Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	$19,739,000	$27,850,000
Derivative liabilities, Gross, offset against assets for presentation in the Balance Sheet	-19,262,000	-18,873,000
Derivative Assets, Current	477,000	5,572,000
Derivative Assets, Noncurrent	'	3,405,000
Derivative assets, net, total	477,000	8,977,000
Derivative Liability, Fair Value, Gross Liability	50,598,000	27,842,000
Derivative assets, Gross, offset against liabilities for presentation in the Balance Sheet	-19,262,000	-18,873,000
Derivative Liabilities, Current	15,967,000	4,483,000
Derivative Liabilities, Noncurrent	15,369,000	4,486,000
Derivative liabilities, net, total	31,336,000	8,969,000
Derivative Assets Current [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	7,444,000	13,218,000
Derivative liabilities, Gross, offset against assets for presentation in the Balance Sheet	-6,967,000	-7,646,000
Derivative Assets, Current	477,000	5,572,000
Derivative Asset Non-Current [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative Asset, Fair Value, Gross Asset	12,295,000	14,632,000
Derivative liabilities, Gross, offset against assets for presentation in the Balance Sheet	-12,295,000	-11,227,000
Derivative Assets, Noncurrent	'	3,405,000
Derivative Liabilities Current [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	22,934,000	12,129,000
Derivative assets, Gross, offset against liabilities for presentation in the Balance Sheet	-6,967,000	-7,646,000
Derivative Liabilities, Current	15,967,000	4,483,000
Derivative Liabilities Non Current [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative Liability, Fair Value, Gross Liability	27,664,000	15,713,000
Derivative assets, Gross, offset against liabilities for presentation in the Balance Sheet	-12,295,000	-11,227,000
Derivative Liabilities, Noncurrent	$15,369,000	$4,486,000

Derivative_Financial_Instrumen4

Derivative Financial Instruments (Effect Of Derivative Instruments In The Consolidated Statements Of Operations) (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Gain (loss) --- oil and natural gas derivative contracts	($24,729)	$26,147	($35,428)	$13,825
Not Designated As Hedging Instrument [Member] | Oil Revenues [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Gain (loss) --- oil and natural gas derivative contracts	-23,541	16,639	-28,510	12,210
Not Designated As Hedging Instrument [Member] | Natural Gas Revenues [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Gain (loss) --- oil and natural gas derivative contracts	($1,188)	$9,508	($6,918)	$1,615

Derivative_Financial_Instrumen5

Derivative Financial Instruments (Natural Gas Derivative Contracts) (Details) (Natural Gas Derivative Contracts [Member])	6 Months Ended
	Jun. 30, 2014
	MMBTU
2014 [Member] | Price Swap Contracts [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	4,755,000
Weighted Average Swap Price	4.41
2014 [Member] | Price Swap Contracts [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Swap Price	5.6
2014 [Member] | Price Swap Contracts [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Swap Price	4.01
2014 [Member] | Short Call Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	5,778,000
Weighted Average Option Price	5.48
2014 [Member] | Short Call Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	9
2014 [Member] | Short Call Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.75
2014 [Member] | Long Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	1,670,000
Weighted Average Option Price	4.86
2014 [Member] | Long Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	6
2014 [Member] | Long Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.25
2014 [Member] | Long Call Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	3,600,901
Weighted Average Option Price	5.77
2014 [Member] | Long Call Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	9
2014 [Member] | Long Call Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.5
2014 [Member] | Short Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	5,227,600
Weighted Average Option Price	3.58
2014 [Member] | Short Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4
2014 [Member] | Short Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	3
2015 [Member] | Price Swap Contracts [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	3,832,500
Weighted Average Swap Price	5.07
2015 [Member] | Price Swap Contracts [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Swap Price	5.91
2015 [Member] | Price Swap Contracts [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Swap Price	4.31
2015 [Member] | Short Call Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	7,750,000
Weighted Average Option Price	4.59
2015 [Member] | Short Call Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	5.75
2015 [Member] | Short Call Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.51
2015 [Member] | Long Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	7,525,000
Weighted Average Option Price	4.05
2015 [Member] | Long Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	5
2015 [Member] | Long Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4
2015 [Member] | Short Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	9,102,500
Weighted Average Option Price	3.32
2015 [Member] | Short Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4.45
2015 [Member] | Short Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	3.25
2016 [Member] | Price Swap Contracts [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	8,418,000
Weighted Average Option Price	4.22
2016 [Member] | Price Swap Contracts [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4.23
2016 [Member] | Price Swap Contracts [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.22
2016 [Member] | Short Call Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	455,000
Weighted Average Option Price	7.5
2016 [Member] | Short Call Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	7.5
2016 [Member] | Short Call Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	7.5
2016 [Member] | Long Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	455,000
Weighted Average Option Price	5.5
2016 [Member] | Long Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	5.5
2016 [Member] | Long Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	5.5
2016 [Member] | Short Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	455,000
Weighted Average Option Price	4
2016 [Member] | Short Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4
2016 [Member] | Short Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4
2017 [Member] | Short Call Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	6,570,000
Weighted Average Option Price	5
2017 [Member] | Short Call Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	5
2017 [Member] | Short Call Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.98
2017 [Member] | Long Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	6,570,000
Weighted Average Option Price	4.5
2017 [Member] | Long Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4.5
2017 [Member] | Long Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.5
2017 [Member] | Short Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	6,570,000
Weighted Average Option Price	4
2017 [Member] | Short Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4
2017 [Member] | Short Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4
2018 [Member] | Short Call Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	5,475,000
Weighted Average Option Price	5.5
2018 [Member] | Short Call Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	5.53
2018 [Member] | Short Call Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	5.48
2018 [Member] | Long Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	5,475,000
Weighted Average Option Price	4.5
2018 [Member] | Long Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4.5
2018 [Member] | Long Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4.5
2018 [Member] | Short Put Options [Member]	'
Derivative [Line Items]	'
Volume in MMbtu	5,475,000
Weighted Average Option Price	4
2018 [Member] | Short Put Options [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	4
2018 [Member] | Short Put Options [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	4

Derivative_Financial_Instrumen6

Derivative Financial Instruments (Oil Derivative Contracts) (Details) (Oil Derivative Contracts [Member])	6 Months Ended
	Jun. 30, 2014
	bbl
Price Swap Contracts [Member] | 2014 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	906,200
Weighted Average Swap Price	95.97
Price Swap Contracts [Member] | 2014 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Swap Price	105.48
Price Swap Contracts [Member] | 2014 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Swap Price	87.5
Price Swap Contracts [Member] | 2015 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	1,404,500
Weighted Average Swap Price	94.36
Price Swap Contracts [Member] | 2015 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Swap Price	99.3
Price Swap Contracts [Member] | 2015 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Swap Price	86.45
Price Swap Contracts [Member] | 2016 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	366,000
Weighted Average Swap Price	93
Price Swap Contracts [Member] | 2016 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Swap Price	94.92
Price Swap Contracts [Member] | 2016 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Swap Price	85.35
Short Call Options [Member] | 2014 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	511,520
Weighted Average Option Price	104
Short Call Options [Member] | 2014 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	111.3
Short Call Options [Member] | 2014 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	97
Short Call Options [Member] | 2015 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	428,850
Weighted Average Option Price	120.81
Short Call Options [Member] | 2015 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	135.98
Short Call Options [Member] | 2015 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	115
Short Call Options [Member] | 2016 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	859,700
Weighted Average Option Price	107.97
Short Call Options [Member] | 2016 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	130
Short Call Options [Member] | 2016 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	103.87
Short Call Options [Member] | 2017 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	744,950
Weighted Average Option Price	107.99
Short Call Options [Member] | 2017 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	113.83
Short Call Options [Member] | 2017 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	104.15
Short Call Options [Member] | 2018 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	307,400
Weighted Average Option Price	104.39
Short Call Options [Member] | 2018 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	104.65
Short Call Options [Member] | 2018 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	104.15
Long Put Options [Member] | 2014 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	519,800
Weighted Average Option Price	91.59
Long Put Options [Member] | 2014 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	95
Long Put Options [Member] | 2014 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	70
Long Put Options [Member] | 2015 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	1,231,850
Weighted Average Option Price	87.15
Long Put Options [Member] | 2015 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	95
Long Put Options [Member] | 2015 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	85
Long Put Options [Member] | 2016 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	859,700
Weighted Average Option Price	85.98
Long Put Options [Member] | 2016 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	95
Long Put Options [Member] | 2016 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	80
Long Put Options [Member] | 2017 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	744,950
Weighted Average Option Price	83.26
Long Put Options [Member] | 2017 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	90
Long Put Options [Member] | 2017 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	80
Long Put Options [Member] | 2018 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	307,400
Weighted Average Option Price	80
Long Put Options [Member] | 2018 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	80
Long Put Options [Member] | 2018 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	80
Long Call Options [Member] | 2014 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	621,920
Weighted Average Option Price	101.83
Long Call Options [Member] | 2014 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	110
Long Call Options [Member] | 2014 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	90
Short Put Options [Member] | 2014 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	573,528
Weighted Average Option Price	74.39
Short Put Options [Member] | 2014 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	80
Short Put Options [Member] | 2014 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	65
Short Put Options [Member] | 2015 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	2,545,850
Weighted Average Option Price	71.11
Short Put Options [Member] | 2015 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	75
Short Put Options [Member] | 2015 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	60
Short Put Options [Member] | 2016 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	859,700
Weighted Average Option Price	65.98
Short Put Options [Member] | 2016 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	75
Short Put Options [Member] | 2016 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	60
Short Put Options [Member] | 2017 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	744,950
Weighted Average Option Price	63.26
Short Put Options [Member] | 2017 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	70
Short Put Options [Member] | 2017 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	60
Short Put Options [Member] | 2018 [Member]	'
Derivative [Line Items]	'
Volume in Bbls	307,400
Weighted Average Option Price	60
Short Put Options [Member] | 2018 [Member] | Maximum [Member]	'
Derivative [Line Items]	'
Option Price	60
Short Put Options [Member] | 2018 [Member] | Minimum [Member]	'
Derivative [Line Items]	'
Option Price	60

Asset_Retirement_Obligations_D

Asset Retirement Obligations (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Asset Retirement Obligations [Abstract]	'	'	'	'	'
Balance, beginning of year	'	'	$56,023,000	'	'
Liabilities incurred	'	'	408,000	'	'
Liabilities settled	'	'	-1,617,000	-716,000	'
Liabilities transferred in sales of properties	'	'	-322,000	'	'
Revisions to estimates	'	'	4,133,000	'	'
Accretion expense	613,000	449,000	1,171,000	892,000	'
Balance, end of period	59,796,000	'	59,796,000	'	'
Less: Current portion	6,450,000	'	6,450,000	'	3,844,000
Long-term portion	53,346,000	'	53,346,000	'	52,179,000
Additions To PPE Included In ARO Revisions	'	'	$2,800,000	'	'

LongTerm_Debt_And_Notes_Payabl2

Long-Term Debt And Notes Payable To Founder (Narrative) (Details) (USD $)

6 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

Jun. 30, 2014

Jun. 30, 2013

Aug. 05, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Credit Facility [Member]

Credit Facility [Member]

Credit Facility [Member]

Credit Facility [Member]

Credit Facility [Member]

Credit Facility [Member]

Credit Facility [Member]

Credit Facility [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Senior Notes [Member]

Notes Payable To Founder [Member]

Notes Payable To Founder [Member]

LIBOR [Member]

Prime [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Prior to October 15, 2014 [Member]

Twelve Mos Beginning October 15, 2014 [Member]

Twelve Mos Beginning October 15, 2015 [Member]

Twelve Mos Beginning October 15, 2016 [Member]

LIBOR [Member]

Prime [Member]

LIBOR [Member]

Prime [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Date of sixth amended and restated credit agreement

'

'

'

'

13-May-10

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Date of maturity of credit facility

'

'

'

'

23-May-16

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility borrowing base

'

'

$350,000,000

'

$285,000,000

$385,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Credit facility applicable interest rate, description

'

'

'

'

'

'

'LIBOR plus applicable margins between 2.00% and 2.75%

'prime rate of Wells Fargo Bank, N. A., plus a margin ranging from 1.00% to 1.75%

'

'

'

'

'

'

'

'

'

'

'

'

Margin interest rate

'

'

'

'

'

'

'

'

2.00%

1.00%

2.75%

1.75%

'

'

'

'

'

'

'

'

Credit facility interest rate

'

'

'

'

2.75%

2.75%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt covenants description

'

'

'

'

'The credit facility contains customary covenants including, among others, defined financial covenants, including minimum working capital levels (the ratio of current assets plus the unused borrowing base, to current liabilities, excluding assets and liabilities related to derivative contracts) of 1.0 to 1.0, minimum coverage of interest expenses of 3.0 to 1.0, and maximum leverage of 4.00 to 1.00. The interest coverage and leverage ratios refer to the ratio of earnings before interest, taxes, depreciation, depletion, amortization, and exploration expense ("EBITDAX", as defined more specifically in the credit agreement) to interest expense and to total debt (as defined), respectively. Financial ratios are calculated quarterly using EBITDAX for the most recent twelve months.

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt covenant compliance description

'

'

'

'

'As of June 30, 2014, we were in compliance with all covenants.

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument collateral

'

'

'

'

'The credit facility matures on MayB 23, 2016 and is secured by substantially all of our oil and gas properties.

'

'

'

'

'

'

'

'The senior notes are unsecured and are general obligations of the Company, and effectively rank junior to any of our existing or future secured indebtedness, which includes the credit facility. The senior notes are unconditionally guaranteed on a senior unsecured basis by each of our material subsidiaries.

'

'

'

'

'

'These founder notes are unsecured and subordinate to all debt. In connection with the March 25, 2014 recapitalization of our Class B partner described in Note 12, the founder notesB were amended and restated to subordinate them to the PIK notes of our Class B partner. The founder notes were also subordinated to the rights of the holders of Class B units to receive distributions under our amended partnership agreement and subordinated to the rights of the holders of Series B Preferred StockB to receive payments.

'

Maturity Date of Debt

'

'

'

'

'

'

'

'

'

'

'

'

15-Oct-18

'

'

'

'

'

31-Dec-21

'

Face value of senior notes issued

450,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stated interest rate of senior notes

'

'

'

'

'

'

'

'

'

'

'

'

9.63%

'

'

'

'

'

'

'

Senior notes interest payable date

'

'

'

'

'

'

'

'

'

'

'

'

'. Interest is payable semi-annually each AprilB 15th and OctoberB 15th

'

'

'

'

'

'

'

Effective rate of interest on senior notes

'

'

'

'

'

'

'

'

'

'

'

'

9.78%

'

'

'

'

'

'

'

Remaining unamortized discount

'

'

'

'

'

'

'

'

'

'

'

'

2,200,000

2,400,000

'

'

'

'

'

'

Optional redemption price of Senior Notes

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

104.81%

102.41%

100.00%

'

'

Optional redemption clause prior to Oct 2014

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'Prior to October 15, 2014, we may redeem the senior notes in whole or in part at a price equal to 100 percent of the principal amount plus a specified make-whole premium and accrued and unpaid interest to the applicable redemption date.

'

'

'

'

'

Notes payable to founder

23,931,000

'

'

23,331,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

23,900,000

23,300,000

Rate of interest on notes payable to founder

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

10.00%

'

Payment terms, notes payable to founder

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'Interest and principal are payable at maturity.

'

Interest on notes payable to founder

$600,000

$599,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Conversion feature, notes payable to founder

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'The notesB are convertible into shares of our Class B partner, Alta Mesa Investment Holdings, Inc., common stock upon certain conditions in the event of an initial public offering.

'

LongTerm_Debt_And_Notes_Payabl3

Long-Term Debt And Notes Payable To Founder (Long-Term Debt) (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Long-Term Debt And Notes Payable To Founder [Abstract]	'	'
Credit Facility	$229,520	$319,290
Senior Notes	447,833	447,578
Total long-term debt	677,353	766,868
Notes payable to founder	$23,931	$23,331

Accounts_Payable_And_Accrued_L2

Accounts Payable And Accrued Liabilities (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accounts Payable And Accrued Liabilities [Abstract]	'	'
Capital expenditures	$28,052	$18,629
Revenues and royalties payable	7,262	9,699
Operating expenses/taxes	20,663	17,071
Interest	9,816	9,146
Compensation	9,019	8,862
Other	9,562	2,711
Total accrued liabilities	84,374	66,118
Accounts payable	25,146	29,977
Accounts payable and accrued liabilities	$109,520	$96,095

Commitments_and_Contingencies_

Commitments and Contingencies (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Commitments And Contingencies [Abstract]	'	'
Liability for soil contamination	$1.10	$1.10

Partners_Capital_Deficit_Detai

Partners' Capital (Deficit) (Details) (USD $)	Jun. 30, 2014
In Millions, unless otherwise specified	employee
	item
Partners' Capital (Deficit) [Abstract]	'
Amount of recapitalization	$350
Number of members added to Board of Directors, nominated by Highbridge	1
Number of employees added as member to board of directors	1