Pioneer Natural Resources (PXD) 10-Q 7 May 15 2015 Q1 Quarterly report Financial data

Document_And_Entity_Informatio

Document And Entity Information	3 Months Ended
	Mar. 31, 2015	4-May-15
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	PXD
Entity Registrant Name	PIONEER NATURAL RESOURCES CO
Entity Central Index Key	1038357
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		149,298,875

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Current assets:
Cash and cash equivalents	$383	$1,025
Accounts receivable:
Trade, net	341	436
Due from affiliates	2	4
Income taxes receivable	22	23
Inventories	266	241
Prepaid expenses	20	15
Other current assets:
Derivatives Assets, Current	624	578
Other	36	37
Total current assets	1,694	2,359
Oil and gas properties, using the successful efforts method of accounting:
Proved properties	16,005	15,662
Unproved properties	162	159
Accumulated depletion, depreciation and amortization	-5,727	-5,431
Total property, plant and equipment	10,440	10,390
Goodwill	272	272
Property, Plant and Equipment, Net	1,406	1,391
Other assets:
Investment in unconsolidated affiliate	259	239
Derivative Assets, Noncurrent	181	181
Other, net	95	94
Assets, Total	14,347	14,926
Accounts payable:
Trade	841	1,197
Due to affiliates	37	123
Interest payable	20	40
Income taxes payable	1	1
Deferred Tax Liabilities, Net, Current	185	161
Other current liabilities:
Derivative Liabilities, Current	16	3
Other	62	55
Total current liabilities	1,162	1,580
Long-term Debt, Excluding Current Maturities	2,668	2,665
Derivative Liabilities, Noncurrent	0	2
Deferred income taxes	1,738	1,803
Other liabilities	280	287
Stockholders' equity:
Common stock, $.01 par value	2	2
Additional paid-in capital	6,190	6,167
Treasury stock at cost	-201	-171
Retained earnings	2,500	2,583
Total equity attributable to common stockholders	8,491	8,581
Noncontrolling interests in consolidating subsidiaries	8	8
Total equity	8,499	8,589
Commitments and contingencies
Liabilities and Stockholders' Equity, Total	$14,347	$14,926

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	500,000,000	500,000,000
Common Stock, Shares, Issued	152,000,000	152,000,000
Treasury Stock, Shares	3,000,000	3,000,000

Consolidated_Statements_Of_Ope

Consolidated Statements Of Operations (USD $)	3 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues and other income:
Oil and gas	$517	$890
Sales of purchased oil and gas	103	147
Interest and other	6	5
Derivative gains (losses), net	241	-104
Gain (loss) on disposition of assets, net	1	6
Total revenues and other income	868	944
Costs and expenses:
Oil and gas production	180	158
Production and ad valorem taxes	39	55
Depletion, depreciation and amortization	310	217
Purchased oil and gas	108	143
Impairment of oil and gas properties	138	0
Exploration and abandonments	25	31
General and administrative	82	81
Accretion of discount on asset retirement obligations	3	3
Interest	46	45
Other	48	15
Costs and Expenses	979	748
Income (loss) from continuing operations before income taxes	-111	196
Income tax benefit (provision)	37	-51
Income (loss) from continuing operations	-74	145
Loss from discontinued operations, net of tax	-4	-22
Net income (loss)	-78	123
Net income (loss) attributable to common stockholders	-78	123
Basic earnings per share:
Income (loss) from continuing operations	($0.50)	$1
Loss from discontinued operations	($0.02)	($0.15)
Net income (loss)	($0.52)	$0.85
Diluted earnings per share:
Income (loss) from continuing operations	($0.50)	$1
Loss from discontinued operations	($0.02)	($0.15)
Net income (loss)	($0.52)	$0.85
Weighted average shares outstanding:
Basic	149	143
Diluted	149	143
Dividends declared per share	$0.04	$0.04
Amounts attributable to common stockholders:
Net income (loss) attributable to common stockholders	($78)	$123

Consolidated_Statement_Of_Equi

Consolidated Statement Of Equity (USD $)	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]
In Millions, unless otherwise specified
Beginning Balance at Dec. 31, 2014	$8,589	$2	$6,167	($171)	$2,583	$8
Beginning Balance, shares at Dec. 31, 2014		149
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared ($0.04 per share)	-5				-5
Treasury stock purchases, shares		0
Treasury stock purchases	-30			-30
Tax benefit related to stock-based compensation	1		1
Compensation costs:
Compensation costs included in net income	22		22			0
Net loss	-78				-78	0
Ending Balance at Mar. 31, 2015	$8,499	$2	$6,190	($201)	$2,500	$8
Ending Balance, shares at Mar. 31, 2015		149

Consolidated_Statement_Of_Equi1

Consolidated Statement Of Equity (Parenthetical) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Statement of Stockholders' Equity [Abstract]
Dividends declared per share	$0.04	$0.04

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income (loss)	($78)	$123
Adjustments to reconcile net income to net cash provided by operating activities:
Depletion, depreciation and amortization	310	217
Impairment of oil and gas properties	138	0
Impairment of Inventory and Other Property and Equipment	6	0
Exploration expenses, including dry holes	5	7
Deferred income taxes	-37	39
Gain on disposition of assets, net	-1	-6
Accretion of discount on asset retirement obligations	3	3
Discontinued operations	-3	103
Interest expense	5	4
Derivative related activity	-35	86
Amortization of stock-based compensation	22	22
Other	-1	7
Change in operating assets and liabilities, net of effects from acquisitions and dispositions:
Accounts receivable, net	96	-37
Income taxes receivable	1	5
Inventories	-34	-16
Prepaid expenses	-5	-1
Other current assets	-7	-3
Accounts payable	-250	-70
Interest payable	-20	-26
Income taxes payable	0	9
Other current liabilities	-11	0
Net cash provided by operating activities	104	466
Cash flows from investing activities:
Proceeds from disposition of assets, net of cash sold	4	86
Additions to oil and gas properties	-658	-664
Additions to other assets and other property and equipment, net	-63	-48
Net cash used in investing activities	-717	-626
Cash flows from financing activities:
Borrowings under long-term debt	0	150
Principal payments on long-term debt	0	-100
Payments of other liabilities	0	-1
Exercise of long-term incentive plan stock options	0	4
Purchases of treasury stock	-30	-31
Excess tax benefits related to stock-based compensation	1	2
Net cash provided by (used in) financing activities	-29	24
Net decrease in cash and cash equivalents	-642	-136
Cash and cash equivalents, beginning of period	1,025	393
Cash and cash equivalents, end of period	$383	$257

Organization_And_Nature_Of_Ope

Organization And Nature Of Operations	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization And Nature Of Operations	Organization and Nature of Operations
	Pioneer Natural Resources Company ("Pioneer" or the "Company") is a Delaware corporation whose common stock is listed and traded on the New York Stock Exchange. The Company is a large independent oil and gas exploration and production company operating in the United States, with operations primarily in the Permian Basin in West Texas, the Eagle Ford Shale play in South Texas, the Raton field in southeastern Colorado and the West Panhandle field in the Texas Panhandle.

Basis_Of_Presentation

Basis Of Presentation	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis Of Presentation	Basis of Presentation
	Presentation. In the opinion of management, the consolidated financial statements of the Company as of March 31, 2015 and for the three months ended March 31, 2015 and 2014 include all adjustments and accruals, consisting only of normal, recurring accrual adjustments, which are necessary for a fair presentation of the results for the interim periods. These interim results are not necessarily indicative of results for a full year.
	Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States ("GAAP") have been condensed in or omitted from this report pursuant to the rules and regulations of the United States Securities and Exchange Commission (the "SEC"). These consolidated financial statements should be read together with the consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2014.
	Certain reclassifications have been made to the 2014 financial statement and footnote amounts in order to conform to the 2015 presentation.
	New accounting pronouncements. In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-03, "Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs." ASU 2015-03 requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. Currently, debt issuance costs are recognized as deferred charges and recorded as assets. The guidance is effective for annual and interim periods beginning after December 15, 2015 with early adoption permitted and is to be implemented retrospectively. Adoption of the new guidance will only affect the presentation of the Company's consolidated balance sheets and will not have a material impact.
	In February 2015, the FASB issued ASU 2015-02, "Consolidation (Topic 810): Amendments to the Consolidation Analysis." ASU 2015-02 affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. ASU 2015-02 is effective for periods beginning after December 15, 2015 with early adoption permitted. The Company is evaluating the new guidance and has not determined the impact this standard may have on its financial statements.
	In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers (Topic 606)," which supersedes the revenue recognition requirements in Accounting Standards Codification ("ASC") Topic 605, "Revenue Recognition," and most industry-specific guidance. ASU 2014-09 is based on the principle that revenue is recognized to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts. ASU 2014-09 applies to all contracts with customers except those that are within the scope of other topics in the FASB ASC. The new guidance is effective for annual reporting periods beginning after December 15, 2016 for public companies, with early adoption not permitted. Entities have the option of using either a full retrospective or modified approach to adopt ASU 2014-09. In April 2015, the FASB issued an exposure draft proposing to defer the effective date until annual reports beginning after December 15, 2017. The Company is currently evaluating the new guidance and has not determined the impact this standard may have on its financial statements or decided upon the method of adoption.
	In April 2014, the FASB issued ASU 2014-08, "Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity." ASU 2014-08 prospectively changes the criteria for reporting discontinued operations while enhancing disclosures around disposals of assets whether or not the disposal meets the definition of a discontinued operation. The Company adopted ASU 2014-08 effective January 1, 2015 for disposals that have not been reported in the Company's previously issued consolidated financial statements. The impact of this guidance on the Company's consolidated financial statements will depend on the magnitude and nature of the Company's disposal transactions in the future.

Acquisitions_and_Divestitures

Acquisitions and Divestitures	3 Months Ended
	Mar. 31, 2015
Acquisitions and Divestitures [Abstract]
Acquisition and Divestitures	Divestitures
	Divestitures Recorded in Continuing Operations
	For the three months ended March 31, 2015 and 2014, the Company recorded net gains on disposition of assets in continuing operations of $1 million and $6 million, respectively, which were primarily comprised of the following:
	•	Vertical drilling rigs. In March 2014, the Company completed the sale of Sendero Drilling Company, LLC ("Sendero") to Sendero's minority interest owner for cash proceeds of $31 million, which resulted in a gain of $1 million. As part of the sales agreement, the Company committed to a lease agreement with Sendero for 12 vertical rigs through December 31, 2015, and eight vertical rigs in 2016. During the three months ended March 31, 2015, the Company incurred $9 million of idle drilling rig fees related to the leased Sendero rigs.
	•	Permian Basin. During February 2014, the Company completed the sale of proved and unproved properties in Gaines and Dawson counties in the Spraberry field in West Texas for cash proceeds of $72 million, which resulted in a gain of $2 million.
	Divestitures Recorded as Discontinued Operations
	During 2014, the Company completed the sales of its (i) net assets in the Hugoton field in southwest Kansas for cash proceeds of $328 million, (ii) net assets in the Barnett Shale field in North Texas for cash proceeds of $150 million and (iii) capital stock in its Alaskan subsidiary ("Pioneer Alaska") for cash proceeds of $267 million. The Company has classified its Hugoton, Barnett Shale and Pioneer Alaska results of operations as income (loss) from discontinued operations, net of tax, in the accompanying consolidated statements of operations.
	The following table represents the components of the Company's discontinued operations for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015			2014
			(in millions)
	Revenues and other income (a)		$	—		$	118
	Costs and expenses (b)		6			152
	Loss from discontinued operations before income taxes		(6		)	(34		)
	Deferred tax benefit		2			12
	Loss from discontinued operations		$	(4	)	$	(22	)
	____________________
	(a)	Primarily comprised of oil and gas revenues and cash received associated with Alaskan Petroleum Production Tax credits on qualifying capital expenditures.
	(b)	Costs and expenses during 2015 were primarily comprised of an arbitration award related to plugging and abandonment obligations associated with two Gulf of Mexico wells from which Pioneer withdrew in 2009. Costs and expenses in 2014 were primarily comprised of oil and gas production costs and impairment charges. See Note D for information about impairment charges on the Barnett Shale assets and Pioneer Alaska.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements
	Fair value is defined as the price that would be received to sell an asset or the price paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value measurements are based upon inputs that market participants use in pricing an asset or liability, which are characterized according to a hierarchy that prioritizes those inputs based on the degree to which they are observable. Observable inputs represent market data obtained from independent sources, whereas unobservable inputs reflect a company's own market assumptions, which are used if observable inputs are not reasonably available without undue cost and effort. The three input levels of the fair value hierarchy are as follows:
	•	Level 1 – quoted prices for identical assets or liabilities in active markets.
	•	Level 2 – quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (e.g., interest rates) and inputs derived principally from or corroborated by observable market data by correlation or other means.
	•	Level 3 – unobservable inputs for the asset or liability.
	Assets and liabilities measured at fair value on a recurring basis. The fair value input hierarchy level to which an asset or liability measurement in its entirety falls is determined based on the lowest level input that is significant to the measurement in its entirety.
	The following table presents the Company's assets and liabilities that are measured at fair value on a recurring basis as of March 31, 2015 for each of the fair value hierarchy levels:
			Fair Value Measurement at March 31, 2015 Using
			Quoted Prices		Significant		Significant		Fair Value at March 31, 2015
			in Active		Other		Unobservable
			Markets for		Observable		Inputs
			Identical		Inputs		(Level 3)
			Assets		(Level 2)
			(Level 1)
			(in millions)
	Assets:
	Commodity derivatives		$	—	$	805	$	—	$	805
	Deferred compensation plan assets		73		—		—		73
	Total assets		73		805		—		878
	Liabilities:
	Commodity derivatives		—		3		—		3
	Interest rate derivatives		—		13		—		13
	Total liabilities		—		16		—		16
	Total recurring fair value measurements		$	73	$	789	$	—	$	862
	Commodity derivatives. The Company's commodity derivatives represent oil, natural gas liquids ("NGL") and gas swap contracts and collar contracts with short puts. The asset and liability measurements for the Company's commodity derivative contracts represent Level 2 inputs in the hierarchy. The Company utilizes discounted cash flow and option-pricing models for valuing its commodity derivatives.
	The asset and liability values attributable to the Company's commodity derivatives were determined based on inputs that include (i) the contracted notional volumes, (ii) independent active market price quotes, (iii) the applicable estimated credit-adjusted risk-free rate yield curve and (iv) the implied rate of volatility inherent in the collar contracts with short puts, which is based on active and independent market-quoted volatility factors.
	Deferred compensation plan assets. The Company's deferred compensation plan assets represent investments in equity and mutual fund securities that are actively traded on major exchanges. These investments are measured based on observable prices on major exchanges. As of March 31, 2015, the significant inputs to these asset values represented Level 1 independent active exchange market price inputs.
	Interest rate derivatives. The Company's interest rate derivative liabilities represent Treasury rate swap contracts. The Company utilizes discounted cash flow models for valuing its interest rate derivatives. The net derivative values attributable to the Company's interest rate derivative contracts are based on (i) the contracted notional amounts, (ii) London Interbank Offered Rate ("LIBOR") yield curves provided by counterparties and corroborated with forward active market-quoted LIBOR yield curves and (iii) the applicable credit-adjusted risk-free rate yield curve. The Company's interest rate derivative fair value measurements represent Level 2 inputs in the hierarchy priority.
	Assets and liabilities measured at fair value on a nonrecurring basis. Certain assets and liabilities are measured at fair value on a nonrecurring basis. These assets and liabilities are not measured at fair value on an ongoing basis, but are subject to fair value adjustments in certain circumstances. These assets and liabilities can include inventory, proved and unproved oil and gas properties and other long-lived assets that are written down to fair value when they are impaired or held for sale. During the three months ended March 31, 2015, the Company recorded charges in other expense in the Company's accompanying consolidated statements of operations of $6 million to reduce the carrying value of inventory to fair value.
	Proved oil and gas properties. During the three months ended March 31, 2015, reductions in management's longer-term commodity price outlooks ("Management's Price Outlooks") provided indications of possible impairment of the Company's oil and gas properties in the West Panhandle field. As a result of management's assessments, during the first quarter of 2015, the Company recognized a pretax noncash impairment charge of $138 million to reduce the carrying value of the West Panhandle field to its estimated fair value.
	The Company calculated the fair value of the West Panhandle field as of March 31, 2015 using a discounted future cash flow model. Significant Level 3 assumptions associated with the calculation of the West Panhandle field's discounted future cash flows as of March 31, 2015 included Management's Price Outlooks for (i) oil prices of $65.02 per barrel ("Bbl") and (ii) gas prices of $3.83 per million British thermal units ("MMBtu") and management's outlooks for (iii) production costs, (iv) capital expenditures, (v) production and (vi) estimated proved reserves and risk-adjusted probable reserves. Management's Price Outlooks are developed based on third-party futures price outlooks as of a measurement date. The expected future net cash flows were discounted using an annual rate of 10 percent to determine estimated fair value.
	Assets associated with divestitures. Long-lived assets that are classified as held for sale are recorded at the lower of the asset's net carrying amount or estimated fair value less costs to sell. The Barnett Shale field assets and Pioneer Alaska were classified as held for sale at December 31, 2013 and carried as such until their divestitures in September 2014 and April 2014, respectively. Associated therewith, during the three months ended March 31, 2014, the Company recognized impairment charges of $14 million and $97 million, respectively, to reduce the carrying values of the Barnett Shale field assets and Pioneer Alaska to their estimated fair values, less costs to sell at March 31, 2014.
	See Note C for additional information regarding the Company's divestitures of the Barnett Shale field assets and Pioneer Alaska.
	Financial instruments not carried at fair value. Carrying values and fair values of financial instruments that are not carried at fair value in the consolidated balance sheets as of March 31, 2015 and December 31, 2014 are as follows:
			March 31, 2015				December 31, 2014
			Carrying		Fair		Carrying		Fair
			Value		Value		Value		Value
			(in millions)
	Long-term debt		$	2,668	$	2,987	$	2,665	$	2,938
	Long-term debt includes the Company's credit facility and the Company's senior notes. The fair value of debt is determined utilizing inputs that are Level 2 measurements in the fair value hierarchy.
	Credit facility. The fair value of the Company's credit facility is calculated using a discounted cash flow model based on (i) forecasted contractual interest and fee payments, (ii) forward active market-quoted United States Treasury Bill rates and (iii) the applicable credit-adjustments.
	Senior notes. The Company's senior notes represent debt securities that are traded on major exchanges but are not actively traded. The fair values of the Company's senior notes are based on their periodic values as quoted on the major exchanges.
	The Company has other financial instruments consisting primarily of cash equivalents, receivables, prepaid expenses, payables and other current assets and liabilities that approximate fair value due to the nature of the instrument and their relatively short maturities. Non-financial assets and liabilities initially measured at fair value include assets acquired and liabilities assumed in a business combination, goodwill and asset retirement obligations.

Derivative_Financial_Instrumen

Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments
	The Company utilizes commodity swap contracts, collar contracts and collar contracts with short puts to (i) reduce the effect of price volatility on the commodities the Company produces and sells or consumes, (ii) support the Company's annual capital budgeting and expenditure plans and (iii) reduce commodity price risk associated with certain capital projects. The Company also, from time to time, utilizes interest rate contracts to reduce the effect of interest rate volatility on the Company's indebtedness.
	Oil production derivative activities. All material physical sales contracts governing the Company's oil production are tied directly to, or are highly correlated with, New York Mercantile Exchange ("NYMEX") West Texas Intermediate ("WTI") oil prices. The Company uses derivative contracts to manage oil price volatility and basis swap contracts to reduce basis risk between NYMEX prices and the actual index prices at which the oil is sold.
	The following table sets forth the volumes per day associated with the Company's outstanding oil derivative contracts as of March 31, 2015 and the weighted average oil prices for those contracts:
			Nine Months Ending December 31,				Year Ending December 31,
			2015				2016
	Swap contracts:
	Volume (Bbl)		82,000				—
	Price per Bbl		$	71.18			$	—
	Collar contracts with short puts:
	Volume (Bbl) (a)(b)		15,000				73,000
	Price per Bbl:
	Ceiling		$	97.69			$	79.48
	Floor		$	82.97			$	69.53
	Short put		$	69.67			$	47.36
	Rollfactor swap contracts:
	Volume (Bbl)		37,000				—
	NYMEX roll price (c)		$	0.06			$	—
	____________________
	(a)	Counterparties have the option to extend for an additional year 5,000 Bbls per day of 2015 collar contracts with short puts with a ceiling price of $100.08 per Bbl, a floor price of $90.00 per Bbl and a short put price of $80.00 per Bbl. The option to extend is exercisable on December 31, 2015. These contracts give the counterparties the option to extend the contracts under the same terms for an additional year if the option to extend is exercised by the counterparties on December 31, 2015.
	(b)	During the period from April 1, 2015 through May 5, 2015, the Company entered into additional oil collar contracts with short puts for 10,000 Bbl per day of 2016 production with a ceiling price of $71.10 per Bbl, a floor price of $60.00 per Bbl and a short put price of $47.50 per Bbl.
	(c)	Represents swaps that fix the difference between (i) each day's price per Bbl of WTI for the first nearby month less (ii) the price per Bbl of WTI for the second nearby NYMEX month, multiplied by .6667; plus (iii) each day's price per Bbl of WTI for the first nearby month less (iv) the price per Bbl of WTI for the third nearby NYMEX month, multiplied by .3333.
	NGL production derivative activities. All material physical sales contracts governing the Company's NGL production are tied directly or indirectly to either Mont Belvieu or Conway fractionation facilities' NGL component product prices.
	The following table sets forth the volumes per day associated with the Company's outstanding NGL derivative contracts as of March 31, 2015 and the weighted average NGL prices for those contracts:
			Nine Months Ending December 31,				Year Ending December 31,
			2015				2016
	Ethane swap contracts:
	Volume (Bbl)		6,000				4,000
	Average price per Bbl		$	7.8			$	12.29
	Propane swap contracts:
	Volume (Bbl)		11,000				2,000
	Average price per Bbl		$	21.62			$	21.63
	Gas production derivative activities. All material physical sales contracts governing the Company's gas production are tied directly or indirectly to NYMEX Henry Hub ("HH") gas prices or regional index prices where the gas is sold. The Company uses derivative contracts to manage gas price volatility and basis swap contracts to reduce basis risk between HH prices and the actual index prices at which the gas is sold.
	The following table sets forth the volumes per day associated with the Company's outstanding gas derivative contracts as of March 31, 2015 and the weighted average gas prices for those contracts:
			Nine Months Ending December 31,				Year Ending December 31,
			2015				2016				2017
	Swap contracts:
	Volume (MMBtu)		20,000				70,000				—
	Price per MMBtu		$	4.31			$	4.06			$	—
	Collar contracts with short puts:
	Volume (MMBtu)		285,000				20,000				—
	Price per MMBtu:
	Ceiling		$	5.07			$	5.36			$	—
	Floor		$	4			$	4			$	—
	Short put		$	3			$	3			$	—
	Basis swap contracts (a):
	Gulf Coast index swap volume		20,000				—				—
	Price differential ($/MMBtu)		$	—			$	—			$	—
	Mid-Continent index swap volume (b)		95,000				15,000				30,000
	Price differential ($/MMBtu)		$	(0.24	)		$	(0.32	)		$	(0.34	)
	Permian Basin index swap volume		10,000				—				—
	Price differential ($/MMBtu)		$	(0.13	)		$	—			$	—
	____________________
	(a)	Represent swaps that fix the basis differentials between the index prices at which the Company sells its Gulf Coast, Mid-Continent and Permian Basin gas, respectively, and the NYMEX Henry Hub index price used in gas swap and collar contracts.
	(b)	During the period from April 1, 2015 through May 5, 2015, the Company entered into additional basis swap contracts for 15,000 MMBtu per day of the Company's 2017 production with a negative price differential of $0.27 per MMBtu between the relevant index price and the NYMEX price.
	Marketing and basis differential derivative activities. Periodically, the Company enters into buy and sell marketing arrangements to fulfill firm pipeline transportation commitments. Associated with these marketing arrangements, the Company may enter into index swaps to mitigate price risk. As of March 31, 2015, the Company had marketing oil index swap contracts for 10,000 Bbl per day for 2015 with a price differential of $2.99 per Bbl between Cushing WTI and LLS. During the period from April 1, 2015 through May 5, 2015, the Company entered into additional oil index swap contracts for 6,000 Bbl per day for June 2015 with a price differential of $5.70 per Bbl between Cushing WTI and LLS.
	Interest rate derivative activities. As of March 31, 2015, the Company was a party to (i) interest rate derivative contracts that expire on June 30, 2015 for a notional amount of $200 million and (ii) interest rate derivative contracts that expire on September 15, 2015 for a notional amount of $150 million. The Company will pay an average fixed rate of 2.43 percent and 2.37 percent, respectively, in exchange for receiving the 10-year Treasury rate as of the expiration date.
	Tabular disclosure of derivative financial instruments. All of the Company's derivatives are accounted for as non-hedge derivatives and therefore all changes in the fair values of its derivative contracts are recognized as gains or losses in the earnings of the periods in which they occur. The Company classifies the fair value amounts of derivative assets and liabilities as net current or noncurrent derivative assets or net current or noncurrent derivative liabilities, whichever the case may be, by commodity and counterparty. The Company enters into derivatives under master netting arrangements, which, in an event of default, allows the Company to offset payables to and receivables from the defaulting counterparty.
	The aggregate fair value of the Company's derivative instruments reported in the consolidated balance sheets by type and counterparty, including the classification between current and noncurrent assets and liabilities, consists of the following:
	Fair Value of Derivative Instruments as of March 31, 2015
	Type		Consolidated Balance Sheet		Fair				Gross Amounts Offset in the Consolidated Balance Sheet				Net Fair Value Presented in the Consolidated Balance Sheet
			Location		Value
					(in millions)
	Derivatives not designated as hedging instruments
Asset Derivatives:
Commodity price derivatives		Derivatives - current		$	627			$	(3	)		$	624
Commodity price derivatives		Derivatives - noncurrent		$	183			$	(2	)		181
												$	805
Liability Derivatives:
Commodity price derivatives		Derivatives - current		$	6			$	(3	)		$	3
Interest rate derivatives		Derivatives - current		$	13			$	—			13
Commodity price derivatives		Derivatives - noncurrent		$	2			$	(2	)		—
												$	16
Fair Value of Derivative Instruments as of December 31, 2014
Type		Consolidated Balance Sheet		Fair				Gross Amounts Offset in the Consolidated Balance Sheet				Net Fair Value Presented in the Consolidated Balance Sheet
		Location		Value
				(in millions)
Derivatives not designated as hedging instruments
Asset Derivatives:
Commodity price derivatives		Derivatives - current		$	579			$	(1	)		$	578
Commodity price derivatives		Derivatives - noncurrent		$	182			$	(1	)		181
												$	759
Liability Derivatives:
Commodity price derivatives		Derivatives - current		$	1			$	(1	)		$	—
Interest rate derivatives		Derivatives - current		$	3			$	—			3
Commodity price derivatives		Derivatives - noncurrent		$	3			$	(1	)		2
												$	5
The Company uses credit and other financial criteria to evaluate the credit standing of, and to select, counterparties to its derivative instruments. Although the Company does not obtain collateral or otherwise secure the fair value of its derivative instruments, associated credit risk is mitigated by the Company's credit risk policies and procedures.
The following table details the location of gains and losses recognized on the Company's derivative contracts in the accompanying consolidated statements of operations:
Derivatives Not Designated as Hedging		Location of Gain / (Loss) Recognized in		Three Months Ended
				March 31,
Instruments		Earnings on Derivatives		2015				2014
			(in millions)
Commodity price derivatives		Derivative gains (losses), net		$	251			$	(114	)
Interest rate derivatives		Derivative gains (losses), net		(10		)		10
Total				$	241			$	(104	)

Exploratory_Costs

Exploratory Costs	3 Months Ended
	Mar. 31, 2015
Exploratory Cost Disclosure [Abstract]
Exploratory Costs	Exploratory Costs
	The Company capitalizes exploratory well and project costs until a determination is made that the well or project has either found proved reserves, is impaired or is sold. The Company's capitalized exploratory well and project costs are presented in proved properties in the accompanying consolidated balance sheets. If the exploratory well or project is determined to be impaired, the impaired costs are charged to exploration and abandonments expense.
	The following table reflects the Company's capitalized exploratory well and project activity during the three months ended March 31, 2015:
		Three Months Ended March 31, 2015
		(in millions)
	Beginning capitalized exploratory costs	$	305
	Additions to exploratory costs pending the determination of proved reserves	226
	Reclassification due to determination of proved reserves	(216		)
	Exploratory well costs charged to exploration expense	(5		)
	Ending capitalized exploratory costs	$	310
	As of March 31, 2015 and December 31, 2014, the Company had no exploratory projects for which exploratory costs have been capitalized for a period greater than one year from the date drilling was completed.

LongTerm_Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Long-Term Debt	Long-term Debt
	The Company's long-term debt consists of senior notes and a revolving corporate credit facility (the "Credit Facility"), including the effects of net deferred fair value hedge losses and issuance discounts. The Credit Facility is maintained with a syndicate of financial institutions and has aggregate loan commitments of $1.5 billion that expire in December 2017. As of March 31, 2015, the Company had no outstanding borrowings under the Credit Facility and was in compliance with all of its debt covenants.

Incentive_Plans

Incentive Plans	3 Months Ended
	Mar. 31, 2015
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Incentive Plans	Incentive Plans
	Stock-based compensation
	For the three months ended March 31, 2015, the Company recorded $29 million of stock-based compensation expense for all plans, as compared to $31 million for the same period of 2014. As of March 31, 2015, there was $200 million of unrecognized compensation expense related to unvested share-based compensation plan awards, including $44 million attributable to stock-based awards that are expected to be settled on their vesting date in cash, rather than in equity shares ("Liability Awards"). The unrecognized compensation expense will be recognized over the remaining vesting periods of the awards, which is a period of less than three years on a weighted average basis. As of March 31, 2015 and December 31, 2014, accounts payable – due to affiliates includes $6 million and $23 million, respectively, of liabilities attributable to Liability Awards.
	The following table summarizes the activity that occurred during the three months ended March 31, 2015, for each type of share-based incentive award issued by Pioneer:
		Restricted		Restricted		Performance	Stock
		Stock Equity		Stock Liability		Units	Options
		Awards		Awards
	Outstanding as of December 31, 2014	1,233,539		328,087		154,733	199,058
	Awards granted	422,966		158,726		82,431	—
	Awards vested	(476,698	)	(160,751	)	—	—
	Awards forfeited	(3,624	)	(7,233	)	—	—
	Outstanding as of March 31, 2015	1,176,183		318,829		237,164	199,058

Asset_Retirement_Obligations

Asset Retirement Obligations	3 Months Ended
	Mar. 31, 2015
Asset Retirement Obligation [Abstract]
Asset Retirement Obligations	Asset Retirement Obligations
	The Company's asset retirement obligations primarily relate to the future plugging and abandonment of wells and facilities. The following table summarizes the Company's asset retirement obligation activity during the three months ended March 31, 2015 and 2014:
		Three Months Ended
		March 31,
		2015			2014
		(in millions)
	Beginning asset retirement obligations	$	189		$	194
	New wells placed on production	1			1
	Changes in estimates	—			1
	Dispositions	—			(1		)
	Liabilities settled	(5		)	(4		)
	Accretion of discount	3			3
	Ending asset retirement obligations	$	188		$	194
	The Company records the current and noncurrent portions of asset retirement obligations in other current liabilities and other liabilities, respectively, in the accompanying consolidated balance sheets. As of March 31, 2015, the current portion of the Company's asset retirement obligations was $31 million, as compared to $28 million at December 31, 2014.

Commitments_And_Contingencies

Commitments And Contingencies	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	Commitments and Contingencies
	The Company is a party to proceedings and claims incidental to its business. While many of these matters involve inherent uncertainty, the Company believes that the amount of the liability, if any, ultimately incurred with respect to such proceedings and claims will not have a material adverse effect on the Company's consolidated financial position as a whole or on its liquidity, capital resources or future annual results of operations. The Company records reserves for contingencies when information available indicates that a loss is probable and the amount of the loss can be reasonably estimated.
	Obligations following divestitures. In connection with its divestiture transactions, the Company may retain certain liabilities and provide the purchaser certain indemnifications, subject to defined limitations, which may apply to identified pre-closing matters, including matters of litigation, environmental contingencies, royalty obligations and income taxes. The Company does not believe these obligations are probable of having a material impact on its liquidity, financial position or future results of operations.

Interest_And_Other_Income

Interest And Other Income	3 Months Ended
	Mar. 31, 2015
Interest and Other Income [Abstract]
Interest And Other Income	Interest and Other Income
	The following table provides the components of the Company's interest and other income for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
		(in millions)
	Deferred compensation plan income		$	3	$	2
	Equity interest in income of EFS Midstream (a)		2		3
	Other income		1		2
	Loss from vertical integration services (b)		—		(2		)
	Total interest and other income		$	6	$	5
	____________________
	(a)	The Company accounts for its investment in EFS Midstream LLC ("EFS Midstream") using the equity method. EFS Midstream is providing gathering, treating and transportation services for the Company during a 20-year contractual term.
	(b)	Loss from vertical integration services primarily represents net margins that result from Company-provided fracture stimulation and related service operations, which are ancillary to and supportive of the Company's oil and gas joint operating activities, and do not represent intercompany transactions. For the three months ended March 31, 2015, these vertical integration net margins included $112 million of revenues and $112 million of costs and expenses. For the same period in 2014, these vertical integration net margins included $92 million of revenues and $94 million of costs and expenses.

Other_Expense

Other Expense	3 Months Ended
	Mar. 31, 2015
Other Expense [Abstract]
Other Expense	Other Expense
	The following table provides the components of the Company's other expense for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
		(in millions)
	Idle drilling and well services equipment charges (a)		$	23	$	—
	Transportation commitment charge (b)		14		11
	Impairment of inventory (c)		6		—
	Other		5		2
	Contingency and environmental accrual adjustments		—		2
	Total other expense		$	48	$	15
	____________________
	(a)	Primarily represents expenses attributable to idle drilling rig fees, which are not chargeable to joint operations.
	(b)	Primarily represents firm transportation payments on excess pipeline capacity commitments.
	(c)	Represents charges to reduce excess material and supplies inventories to their market values. See Note D for additional information on the fair value of materials and supplies inventory.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes
	The Company's income tax benefit (provision) attributable to income from continuing operations consisted of the following for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
		(in millions)
	Current tax provision		$	—	$	(12	)
	Deferred tax benefit (provision)		37		(39		)
	Income tax benefit (provision)		$	37	$	(51	)
	For the three months ended March 31, 2015, the Company's effective tax rate, excluding income attributable to noncontrolling interests, was 33 percent, as compared to an effective rate of 26 percent for the same period in 2014. The Company's effective tax rates differed from the U.S. statutory rate of 35 percent primarily due to state income tax apportionments, nondeductible expenses and, for the three months ended March 31, 2014, the recognition of a $21 million tax benefit resulting from the resolution during the first quarter of 2014 of a tax uncertainty related to net operating loss carryovers and alternative minimum tax credits obtained from the 2012 acquisition of Premier Silica. The Company has no unrecognized tax benefits as of March 31, 2015.
	The Company files income tax returns in the U.S. federal and various state and foreign jurisdictions. The Internal Revenue Service has closed examinations of the 2012 and prior tax years and, with few exceptions, the Company believes that it is no longer subject to examinations by state and foreign tax authorities for years before 2009. As of March 31, 2015, no adjustments had been proposed in any jurisdiction that would have a significant effect on the Company's liquidity, future results of operations or financial position.

Net_Income_Per_Share

Net Income Per Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Net Income Per Share	Net Income (Loss) Per Share
	The following table reconciles the Company's income (loss) from continuing operations to basic and diluted net income (loss) attributable to common stockholders for the three months ended March 31, 2015 and 2014:
		Three Months Ended
		March 31,
		2015			2014
		(in millions)
	Income (loss) from continuing operations	$	(74	)	$	145
	Participating basic earnings	—			(1		)
	Basic and diluted income (loss) from continuing operations	(74		)	144
	Basic and diluted loss from discontinued operations	$	(4	)	$	(22	)
	Basic and diluted net income (loss) attributable to common stockholders	$	(78	)	$	122
	Basic and diluted weighted average common shares outstanding were 149 million for the three months ended March 31, 2015 and 143 million for the three months ended March 31, 2014.

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events
	Restructuring. On May 4, 2015, the Company announced plans to restructure its operations in Colorado, including closing its office in Denver, Colorado and eliminating its Trinidad-based pumping services operations. The Company also expects to relocate a number of employees from Denver to its corporate headquarters in Irving, Texas. This initiative is expected to be substantially completed by the end of the third quarter of 2015.
	The Company estimates that it will incur $15 million to $30 million of one-time restructuring costs in connection with this plan, primarily made up of employee severance and relocation costs.
	EFS Midstream. During November 2014, the Company announced that it is pursuing the divestment of its 50.1 percent share of EFS Midstream. The Company accounts for EFS Midstream under the equity method of accounting for investments in unconsolidated affiliates. The Company is continuing to make progress towards divesting its equity investment in EFS Midstream; however, no assurance can be given that the sale will be completed in accordance with the Company's plans or on terms and at a price acceptable to the Company.

Basis_Of_Presentation_Policies

Basis Of Presentation (Policies)	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Presentation	Presentation. In the opinion of management, the consolidated financial statements of the Company as of March 31, 2015 and for the three months ended March 31, 2015 and 2014 include all adjustments and accruals, consisting only of normal, recurring accrual adjustments, which are necessary for a fair presentation of the results for the interim periods. These interim results are not necessarily indicative of results for a full year.
	Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States ("GAAP") have been condensed in or omitted from this report pursuant to the rules and regulations of the United States Securities and Exchange Commission (the "SEC"). These consolidated financial statements should be read together with the consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2014.
	Certain reclassifications have been made to the 2014 financial statement and footnote amounts in order to conform to the 2015 presentation.
New Accounting Pronouncements, Policy [Policy Text Block]	New accounting pronouncements. In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-03, "Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs." ASU 2015-03 requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. Currently, debt issuance costs are recognized as deferred charges and recorded as assets. The guidance is effective for annual and interim periods beginning after December 15, 2015 with early adoption permitted and is to be implemented retrospectively. Adoption of the new guidance will only affect the presentation of the Company's consolidated balance sheets and will not have a material impact.
	In February 2015, the FASB issued ASU 2015-02, "Consolidation (Topic 810): Amendments to the Consolidation Analysis." ASU 2015-02 affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. ASU 2015-02 is effective for periods beginning after December 15, 2015 with early adoption permitted. The Company is evaluating the new guidance and has not determined the impact this standard may have on its financial statements.
	In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers (Topic 606)," which supersedes the revenue recognition requirements in Accounting Standards Codification ("ASC") Topic 605, "Revenue Recognition," and most industry-specific guidance. ASU 2014-09 is based on the principle that revenue is recognized to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts. ASU 2014-09 applies to all contracts with customers except those that are within the scope of other topics in the FASB ASC. The new guidance is effective for annual reporting periods beginning after December 15, 2016 for public companies, with early adoption not permitted. Entities have the option of using either a full retrospective or modified approach to adopt ASU 2014-09. In April 2015, the FASB issued an exposure draft proposing to defer the effective date until annual reports beginning after December 15, 2017. The Company is currently evaluating the new guidance and has not determined the impact this standard may have on its financial statements or decided upon the method of adoption.
	In April 2014, the FASB issued ASU 2014-08, "Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity." ASU 2014-08 prospectively changes the criteria for reporting discontinued operations while enhancing disclosures around disposals of assets whether or not the disposal meets the definition of a discontinued operation. The Company adopted ASU 2014-08 effective January 1, 2015 for disposals that have not been reported in the Company's previously issued consolidated financial statements. The impact of this guidance on the Company's consolidated financial statements will depend on the magnitude and nature of the Company's disposal transactions in the future.

Acquisitions_and_Divestitures_

Acquisitions and Divestitures (Tables)	3 Months Ended
	Mar. 31, 2015
Acquisitions and Divestitures [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Table Text Block]	The following table represents the components of the Company's discontinued operations for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015			2014
			(in millions)
	Revenues and other income (a)		$	—		$	118
	Costs and expenses (b)		6			152
	Loss from discontinued operations before income taxes		(6		)	(34		)
	Deferred tax benefit		2			12
	Loss from discontinued operations		$	(4	)	$	(22	)
	____________________
	(a)	Primarily comprised of oil and gas revenues and cash received associated with Alaskan Petroleum Production Tax credits on qualifying capital expenditures.
	(b)	Costs and expenses during 2015 were primarily comprised of an arbitration award related to plugging and abandonment obligations associated with two Gulf of Mexico wells from which Pioneer withdrew in 2009. Costs and expenses in 2014 were primarily comprised of oil and gas production costs and impairment charges. See Note D for information about impairment charges on the Barnett Shale assets and Pioneer Alaska.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Schedule of assets and liabilities measured at fair value on a recurring basis	The following table presents the Company's assets and liabilities that are measured at fair value on a recurring basis as of March 31, 2015 for each of the fair value hierarchy levels:
		Fair Value Measurement at March 31, 2015 Using
		Quoted Prices		Significant		Significant		Fair Value at March 31, 2015
		in Active		Other		Unobservable
		Markets for		Observable		Inputs
		Identical		Inputs		(Level 3)
		Assets		(Level 2)
		(Level 1)
		(in millions)
	Assets:
	Commodity derivatives	$	—	$	805	$	—	$	805
	Deferred compensation plan assets	73		—		—		73
	Total assets	73		805		—		878
	Liabilities:
	Commodity derivatives	—		3		—		3
	Interest rate derivatives	—		13		—		13
	Total liabilities	—		16		—		16
	Total recurring fair value measurements	$	73	$	789	$	—	$	862
Schedule of carrying values and financial instruments not carried at fair value	Carrying values and fair values of financial instruments that are not carried at fair value in the consolidated balance sheets as of March 31, 2015 and December 31, 2014 are as follows:
		March 31, 2015				December 31, 2014
		Carrying		Fair		Carrying		Fair
		Value		Value		Value		Value
		(in millions)
	Long-term debt	$	2,668	$	2,987	$	2,665	$	2,938

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of oil derivative contracts volume and weighted average price	The following table sets forth the volumes per day associated with the Company's outstanding oil derivative contracts as of March 31, 2015 and the weighted average oil prices for those contracts:
			Nine Months Ending December 31,				Year Ending December 31,
			2015				2016
	Swap contracts:
	Volume (Bbl)		82,000				—
	Price per Bbl		$	71.18			$	—
	Collar contracts with short puts:
	Volume (Bbl) (a)(b)		15,000				73,000
	Price per Bbl:
	Ceiling		$	97.69			$	79.48
	Floor		$	82.97			$	69.53
	Short put		$	69.67			$	47.36
	Rollfactor swap contracts:
	Volume (Bbl)		37,000				—
	NYMEX roll price (c)		$	0.06			$	—
	____________________
	(a)	Counterparties have the option to extend for an additional year 5,000 Bbls per day of 2015 collar contracts with short puts with a ceiling price of $100.08 per Bbl, a floor price of $90.00 per Bbl and a short put price of $80.00 per Bbl. The option to extend is exercisable on December 31, 2015. These contracts give the counterparties the option to extend the contracts under the same terms for an additional year if the option to extend is exercised by the counterparties on December 31, 2015.
	(b)	During the period from April 1, 2015 through May 5, 2015, the Company entered into additional oil collar contracts with short puts for 10,000 Bbl per day of 2016 production with a ceiling price of $71.10 per Bbl, a floor price of $60.00 per Bbl and a short put price of $47.50 per Bbl.
	(c)	Represents swaps that fix the difference between (i) each day's price per Bbl of WTI for the first nearby month less (ii) the price per Bbl of WTI for the second nearby NYMEX month, multiplied by .6667; plus (iii) each day's price per Bbl of WTI for the first nearby month less (iv) the price per Bbl of WTI for the third nearby NYMEX month, multiplied by .3333.
Schedule of NGL derivative volumes and weighted average prices	The following table sets forth the volumes per day associated with the Company's outstanding NGL derivative contracts as of March 31, 2015 and the weighted average NGL prices for those contracts:
			Nine Months Ending December 31,				Year Ending December 31,
			2015				2016
	Ethane swap contracts:
	Volume (Bbl)		6,000				4,000
	Average price per Bbl		$	7.8			$	12.29
	Propane swap contracts:
	Volume (Bbl)		11,000				2,000
	Average price per Bbl		$	21.62			$	21.63
Schedule of gas derivative volume and weighted average prices	The following table sets forth the volumes per day associated with the Company's outstanding gas derivative contracts as of March 31, 2015 and the weighted average gas prices for those contracts:
			Nine Months Ending December 31,				Year Ending December 31,
			2015				2016				2017
	Swap contracts:
	Volume (MMBtu)		20,000				70,000				—
	Price per MMBtu		$	4.31			$	4.06			$	—
	Collar contracts with short puts:
	Volume (MMBtu)		285,000				20,000				—
	Price per MMBtu:
	Ceiling		$	5.07			$	5.36			$	—
	Floor		$	4			$	4			$	—
	Short put		$	3			$	3			$	—
	Basis swap contracts (a):
	Gulf Coast index swap volume		20,000				—				—
	Price differential ($/MMBtu)		$	—			$	—			$	—
	Mid-Continent index swap volume (b)		95,000				15,000				30,000
	Price differential ($/MMBtu)		$	(0.24	)		$	(0.32	)		$	(0.34	)
	Permian Basin index swap volume		10,000				—				—
	Price differential ($/MMBtu)		$	(0.13	)		$	—			$	—
	____________________
	(a)	Represent swaps that fix the basis differentials between the index prices at which the Company sells its Gulf Coast, Mid-Continent and Permian Basin gas, respectively, and the NYMEX Henry Hub index price used in gas swap and collar contracts.
	(b)	During the period from April 1, 2015 through May 5, 2015, the Company entered into additional basis swap contracts for 15,000 MMBtu per day of the Company's 2017 production with a negative price differential of $0.27 per MMBtu between the relevant index price and the NYMEX price.
Offsetting Asset and Liability	The aggregate fair value of the Company's derivative instruments reported in the consolidated balance sheets by type and counterparty, including the classification between current and noncurrent assets and liabilities, consists of the following:
	Fair Value of Derivative Instruments as of March 31, 2015
	Type		Consolidated Balance Sheet		Fair				Gross Amounts Offset in the Consolidated Balance Sheet				Net Fair Value Presented in the Consolidated Balance Sheet
			Location		Value
					(in millions)
	Derivatives not designated as hedging instruments
	Asset Derivatives:
	Commodity price derivatives		Derivatives - current		$	627			$	(3	)		$	624
	Commodity price derivatives		Derivatives - noncurrent		$	183			$	(2	)		181
													$	805
	Liability Derivatives:
	Commodity price derivatives		Derivatives - current		$	6			$	(3	)		$	3
	Interest rate derivatives		Derivatives - current		$	13			$	—			13
	Commodity price derivatives		Derivatives - noncurrent		$	2			$	(2	)		—
													$	16
	Fair Value of Derivative Instruments as of December 31, 2014
	Type		Consolidated Balance Sheet		Fair				Gross Amounts Offset in the Consolidated Balance Sheet				Net Fair Value Presented in the Consolidated Balance Sheet
			Location		Value
					(in millions)
	Derivatives not designated as hedging instruments
	Asset Derivatives:
	Commodity price derivatives		Derivatives - current		$	579			$	(1	)		$	578
	Commodity price derivatives		Derivatives - noncurrent		$	182			$	(1	)		181
													$	759
	Liability Derivatives:
	Commodity price derivatives		Derivatives - current		$	1			$	(1	)		$	—
	Interest rate derivatives		Derivatives - current		$	3			$	—			3
	Commodity price derivatives		Derivatives - noncurrent		$	3			$	(1	)		2
													$	5
Schedule of derivative gains and losses recognized on statement of operations	The following table details the location of gains and losses recognized on the Company's derivative contracts in the accompanying consolidated statements of operations:
	Derivatives Not Designated as Hedging		Location of Gain / (Loss) Recognized in		Three Months Ended
					March 31,
	Instruments		Earnings on Derivatives		2015				2014
				(in millions)
	Commodity price derivatives		Derivative gains (losses), net		$	251			$	(114	)
	Interest rate derivatives		Derivative gains (losses), net		(10		)		10
	Total				$	241			$	(104	)

Exploratory_Costs_Tables

Exploratory Costs (Tables)	3 Months Ended
	Mar. 31, 2015
Exploratory Cost Disclosure [Abstract]
Capitalized exploratory well and project activity	The following table reflects the Company's capitalized exploratory well and project activity during the three months ended March 31, 2015:
		Three Months Ended March 31, 2015
		(in millions)
	Beginning capitalized exploratory costs	$	305
	Additions to exploratory costs pending the determination of proved reserves	226
	Reclassification due to determination of proved reserves	(216		)
	Exploratory well costs charged to exploration expense	(5		)
	Ending capitalized exploratory costs	$	310

Incentive_Plans_Tables

Incentive Plans (Tables)	3 Months Ended
	Mar. 31, 2015
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Schedule of Share Based Incentive Award Activity	The following table summarizes the activity that occurred during the three months ended March 31, 2015, for each type of share-based incentive award issued by Pioneer:
		Restricted		Restricted		Performance	Stock
		Stock Equity		Stock Liability		Units	Options
		Awards		Awards
	Outstanding as of December 31, 2014	1,233,539		328,087		154,733	199,058
	Awards granted	422,966		158,726		82,431	—
	Awards vested	(476,698	)	(160,751	)	—	—
	Awards forfeited	(3,624	)	(7,233	)	—	—
	Outstanding as of March 31, 2015	1,176,183		318,829		237,164	199,058

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	3 Months Ended
	Mar. 31, 2015
Asset Retirement Obligation [Abstract]
Schedule of asset retirement obligations	The following table summarizes the Company's asset retirement obligation activity during the three months ended March 31, 2015 and 2014:
		Three Months Ended
		March 31,
		2015			2014
		(in millions)
	Beginning asset retirement obligations	$	189		$	194
	New wells placed on production	1			1
	Changes in estimates	—			1
	Dispositions	—			(1		)
	Liabilities settled	(5		)	(4		)
	Accretion of discount	3			3
	Ending asset retirement obligations	$	188		$	194

Interest_And_Other_Income_Tabl

Interest And Other Income (Tables)	3 Months Ended
	Mar. 31, 2015
Interest and Other Income [Abstract]
Components of interest and other income	The following table provides the components of the Company's interest and other income for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
		(in millions)
	Deferred compensation plan income		$	3	$	2
	Equity interest in income of EFS Midstream (a)		2		3
	Other income		1		2
	Loss from vertical integration services (b)		—		(2		)
	Total interest and other income		$	6	$	5
	____________________
	(a)	The Company accounts for its investment in EFS Midstream LLC ("EFS Midstream") using the equity method. EFS Midstream is providing gathering, treating and transportation services for the Company during a 20-year contractual term.
	(b)	Loss from vertical integration services primarily represents net margins that result from Company-provided fracture stimulation and related service operations, which are ancillary to and supportive of the Company's oil and gas joint operating activities, and do not represent intercompany transactions. For the three months ended March 31, 2015, these vertical integration net margins included $112 million of revenues and $112 million of costs and expenses. For the same period in 2014, these vertical integration net margins included $92 million of revenues and $94 million of costs and expenses.

Other_Expense_Tables

Other Expense (Tables)	3 Months Ended
	Mar. 31, 2015
Other Expense [Abstract]
Schedule of components of other expense	The following table provides the components of the Company's other expense for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
		(in millions)
	Idle drilling and well services equipment charges (a)		$	23	$	—
	Transportation commitment charge (b)		14		11
	Impairment of inventory (c)		6		—
	Other		5		2
	Contingency and environmental accrual adjustments		—		2
	Total other expense		$	48	$	15
	____________________
	(a)	Primarily represents expenses attributable to idle drilling rig fees, which are not chargeable to joint operations.
	(b)	Primarily represents firm transportation payments on excess pipeline capacity commitments.
	(c)	Represents charges to reduce excess material and supplies inventories to their market values. See Note D for additional information on the fair value of materials and supplies inventory.

Income_Taxes_Tables

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income tax (provisions) benefits attributable to income from continuing operations	The Company's income tax benefit (provision) attributable to income from continuing operations consisted of the following for the three months ended March 31, 2015 and 2014:
			Three Months Ended
			March 31,
			2015		2014
		(in millions)
	Current tax provision		$	—	$	(12	)
	Deferred tax benefit (provision)		37		(39		)
	Income tax benefit (provision)		$	37	$	(51	)

Net_Income_Per_Share_Tables

Net Income Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Reconciliation of earnings attributable to common stockholders, basic and diluted	The following table reconciles the Company's income (loss) from continuing operations to basic and diluted net income (loss) attributable to common stockholders for the three months ended March 31, 2015 and 2014:
		Three Months Ended
		March 31,
		2015			2014
		(in millions)
	Income (loss) from continuing operations	$	(74	)	$	145
	Participating basic earnings	—			(1		)
	Basic and diluted income (loss) from continuing operations	(74		)	144
	Basic and diluted loss from discontinued operations	$	(4	)	$	(22	)
	Basic and diluted net income (loss) attributable to common stockholders	$	(78	)	$	122

Acquisitions_and_Divestitures_1

Acquisitions and Divestitures (Narrative) (Details) (USD $)	3 Months Ended				12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014		Dec. 31, 2014
Acquisitions and Divestitures [Line Items]
Gain (loss) on disposition of assets, net	$1		$6
Tangible asset impairment	6	[1]	0	[1]
Idle Rig Expense	23	[2]	0	[2]
Proceeds from Sale of Productive Assets	4		86
Impairment of oil and gas properties	138		0
Sendero [Member]
Acquisitions and Divestitures [Line Items]
Gain (loss) on disposition of assets, net			1
Proceeds from Divestiture of Interest in Consolidated Subsidiaries			31
Idle Rig Expense	9
Gaines Dawson [Member]
Acquisitions and Divestitures [Line Items]
Gain (loss) on disposition of assets, net			2
Proceeds from Sale of Productive Assets			72
Lease Contract through Year 2 [Member]
Acquisitions and Divestitures [Line Items]
Drilling rigs leased			12
Lease Contract for Year 3 [Member]
Acquisitions and Divestitures [Line Items]
Drilling rigs leased			8
Discontinued Operations [Member] | Hugoton field [Member]
Acquisitions and Divestitures [Line Items]
Proceeds from Sale of Productive Assets					328
Discontinued Operations [Member] | Pioneer Alaska [Member]
Acquisitions and Divestitures [Line Items]
Proceeds from Sale of Productive Assets					267
Discontinued Operations [Member] | Barnett Shale Field [Member]
Acquisitions and Divestitures [Line Items]
Proceeds from Sale of Productive Assets					$150
[1]	Represents charges to reduce excess material and supplies inventories to their market values. See Note D for additional information on the fair value of materials and supplies inventory.
[2]	Primarily represents expenses attributable to idle drilling rig fees, which are not chargeable to joint operations.

Acquisitions_and_Divestitures_2

Acquisitions and Divestitures Acquisitions and Divestitures (Components of Discontinued Operations) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Oil and gas	$517	$890
Interest and other	6	5
Gain on disposition of assets, net	-1	-6
Oil and gas production	180	158
Production and ad valorem taxes	39	55
Depletion, depreciation and amortization	310	217
Impairment of oil and gas properties	138	0
Exploration and abandonment	25	31
General and administrative	82	81
Asset Retirement Obligation, Accretion Expense	3	3
Other Nonoperating Expense	48	15
Costs and Expenses	979	748
Current tax provision	0	-12
Deferred tax benefit	37	-39
Income (Loss) from Discontinued Operations, Net of Tax	-4	-22
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total Revenues And Other Income From Discontinued Operations	0	118
Costs and Expenses	6	152
Loss from discontinued operations before income taxes	-6	-34
Deferred tax benefit	2	12
Income (Loss) from Discontinued Operations, Net of Tax	($4)	($22)

Fair_Value_Measurements_Schedu

Fair Value Measurements (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $)	Mar. 31, 2015
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred Compensation Plan Assets	$73
Assets, Fair Value Disclosure	878
Liabilities, Fair Value Disclosure	16
Recurring Measurements, (Fair Value, Total)	862
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred Compensation Plan Assets	73
Assets, Fair Value Disclosure	73
Liabilities, Fair Value Disclosure	0
Recurring Measurements, (Fair Value, Total)	73
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred Compensation Plan Assets	0
Assets, Fair Value Disclosure	805
Liabilities, Fair Value Disclosure	16
Recurring Measurements, (Fair Value, Total)	789
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred Compensation Plan Assets	0
Assets, Fair Value Disclosure	0
Liabilities, Fair Value Disclosure	0
Recurring Measurements, (Fair Value, Total)	0
Interest Rate Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value, Net	13
Interest Rate Derivatives [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value, Net	0
Interest Rate Derivatives [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value, Net	13
Interest Rate Derivatives [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value, Net	0
Commodity Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Net	805
Derivative Liability, Fair Value, Net	3
Commodity Derivatives [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Net	0
Derivative Liability, Fair Value, Net	0
Commodity Derivatives [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Net	805
Derivative Liability, Fair Value, Net	3
Commodity Derivatives [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Net	0
Derivative Liability, Fair Value, Net	$0

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value Measurements (Nonrecurring Fair Value Measurements) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory Write-down	$6
Impairment of oil and gas properties	138	0
Management oil price outlook	65.02
Management gas price outlook	3.83
West Panhandle [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of oil and gas properties	138
Discontinued Operations [Member] | Pioneer Alaska [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of oil and gas properties		-97
Discontinued Operations [Member] | Barnett Shale Field [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of oil and gas properties		($14)

Fair_Value_Measurements_Schedu1

Fair Value Measurements (Schedule Of Carrying Values And Financial Instruments Not Carried At Fair Value) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Excluding Current Maturities	$2,668	$2,665
Reported Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Excluding Current Maturities	2,668	2,665
Estimate of Fair Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Excluding Current Maturities	$2,987	$2,938

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Narrative) (Details) (USD $)	Mar. 31, 2015
In Millions, unless otherwise specified
June 30, 2015 Interest Rate Swaps [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Derivative, Fixed Interest Rate	2.43%
Notional amount of debt	$200
September 30, 2015 Interest Rate Swaps [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Derivative, Fixed Interest Rate	2.37%
Notional amount of debt	$150

Derivative_Financial_Instrumen3

Derivative Financial Instruments (Schedule Of Oil Derivative Contracts Volume And Weighted Average Prices) (Details)	Mar. 31, 2015		5-May-15
Rollfactor Swap Contracts [Member]
Derivative [Line Items]
NYMEX swap multiple, second nearby month	0.6667
NYMEX swap multiple, third nearby month	0.3333
Oil contracts [Member] | Collar Contracts With Short Puts for Current Year [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	15,000	[1]
Oil contracts [Member] | Collar Contracts With Short Puts for Year 2 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	73,000	[1],[2]
Oil contracts [Member] | Collar Contracts With Short Puts for Year 2 - Extendible for Year 3 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	5,000
Oil contracts [Member] | Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	82,000
Oil contracts [Member] | Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Oil contracts [Member] | Rollfactor Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	37,000
Oil contracts [Member] | Rollfactor Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Current Year [Member]
Derivative [Line Items]
Derivative, Average Cap Price	97.69
Derivative, Average Floor Price	82.97
Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Current Year [Member] | Short Put [Member]
Derivative [Line Items]
Derivative, Notional Amount, Price Per Unit	69.67
Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Year 2 [Member]
Derivative [Line Items]
Derivative, Average Cap Price	79.48
Derivative, Average Floor Price	69.53
Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Year 2 [Member] | Short Put [Member]
Derivative [Line Items]
Derivative, Notional Amount, Price Per Unit	47.36
Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Year 2 - Extendible for Year 3 [Member]
Derivative [Line Items]
Derivative, Average Cap Price	100.08
Derivative, Average Floor Price	90
Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Year 2 - Extendible for Year 3 [Member] | Short Put [Member]
Derivative [Line Items]
Derivative, Notional Amount, Price Per Unit	80
Oil contracts, price per bbl [Member] | Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	71.18
Oil contracts, price per bbl [Member] | Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0
Oil contracts, price per bbl [Member] | Rollfactor Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0.06	[3]
Oil contracts, price per bbl [Member] | Rollfactor Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0	[3]
Subsequent Event [Member] | Oil contracts [Member] | Collar Contracts With Short Puts for Year 2 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount			10,000	[1]
Subsequent Event [Member] | Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Year 2 [Member]
Derivative [Line Items]
Derivative, Average Cap Price			71.1
Derivative, Average Floor Price			60
Subsequent Event [Member] | Oil contracts, price per bbl [Member] | Collar Contracts With Short Puts for Year 2 [Member] | Short Put [Member]
Derivative [Line Items]
Derivative, Notional Amount, Price Per Unit			47.5
[1]	(a)Counterparties have the option to extend for an additional year 5,000 Bbls per day of 2015 collar contracts with short puts with a ceiling price of $100.08 per Bbl, a floor price of $90.00 per Bbl and a short put price of $80.00 per Bbl. The option to extend is exercisable on December 31, 2015. These contracts give the counterparties the option to extend the contracts under the same terms for an additional year if the option to extend is exercised by the counterparties on December 31, 2015.
[2]	(b)During the period from April 1, 2015 through May 5, 2015, the Company entered into additional oil collar contracts with short puts for 10,000 Bbl per day of 2016 production with a ceiling price of $71.10 per Bbl, a floor price of $60.00 per Bbl and a short put price of $47.50 per Bbl.
[3]	Represents swaps that fix the difference between (i)B each day's price per Bbl of WTI for the first nearby month less (ii)B the price per Bbl of WTI for the second nearby NYMEX month, multiplied by .6667; plus (iii)B each day's price per Bbl of WTI for the first nearby month less (iv)B the price per Bbl of WTI for the third nearby NYMEX month, multiplied by .3333.

Derivative_Financial_Instrumen4

Derivative Financial Instruments Derivative Financial Instruments (Schedule of NGL Derivative Contracts Volume and Weighted Average Prices) (Details)	Mar. 31, 2015
Ethane [Member] | NGL contract, in BBLS [Member] | Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	6,000
Ethane [Member] | NGL contract, in BBLS [Member] | Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	4,000
Ethane [Member] | NGL contracts, price per BBL [Member] | Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	7.8
Ethane [Member] | NGL contracts, price per BBL [Member] | Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	12.29
Propane [Member] | NGL contract, in BBLS [Member] | Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	11,000
Propane [Member] | NGL contract, in BBLS [Member] | Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	2,000
Propane [Member] | NGL contracts, price per BBL [Member] | Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	21.62
Propane [Member] | NGL contracts, price per BBL [Member] | Swap Contracts for Year 2 [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	21.63

Derivative_Financial_Instrumen5

Derivative Financial Instruments Derivative Financial Instruments (Schedule of Gas Derivative Contracts Volume and Weighted Average Prices) (Details)	Mar. 31, 2015		5-May-15
Collar Contracts With Short Puts for Current Year [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	285,000
Collar Contracts With Short Puts for Current Year [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Average Cap Price	5.07
Derivative, Average Floor Price	4
Collar Contracts With Short Puts for Current Year [Member] | Gas contracts, price per MMBTU [Member] | Short Put [Member]
Derivative [Line Items]
Derivative, Notional Amount, Price Per Unit	3
Collar Contracts With Short Puts for Year 2 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	20,000
Collar Contracts With Short Puts for Year 2 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Average Cap Price	5.36
Derivative, Average Floor Price	4
Collar Contracts With Short Puts for Year 2 [Member] | Gas contracts, price per MMBTU [Member] | Short Put [Member]
Derivative [Line Items]
Derivative, Notional Amount, Price Per Unit	3
Collar Contracts With Short Puts for Year 3 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Collar Contracts With Short Puts for Year 3 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Average Cap Price	0
Derivative, Average Floor Price	0
Collar Contracts With Short Puts for Year 3 [Member] | Gas contracts, price per MMBTU [Member] | Short Put [Member]
Derivative [Line Items]
Derivative, Notional Amount, Price Per Unit	0
Swap Contracts for Current Year [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	20,000
Swap Contracts for Current Year [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	4.31
Swap Contracts for Year 2 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	70,000
Swap Contracts for Year 2 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	4.06
Swap Contracts for Year 3 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0
Swap Contracts for Year 3 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0
Gulf Coast [Member] | Basis Swap Contracts for Current Year [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	20,000	[1]
Gulf Coast [Member] | Basis Swap Contracts for Current Year [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0
Gulf Coast [Member] | Basis Swap Contracts for Year 2 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0	[1]
Gulf Coast [Member] | Basis Swap Contracts for Year 2 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0
Gulf Coast [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0	[1]
Gulf Coast [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0
Mid-Continent [Member] | Basis Swap Contracts for Current Year [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	95,000	[1]
Mid-Continent [Member] | Basis Swap Contracts for Current Year [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	-0.24
Mid-Continent [Member] | Basis Swap Contracts for Year 2 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	15,000	[1]
Mid-Continent [Member] | Basis Swap Contracts for Year 2 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	-0.32
Mid-Continent [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	30,000	[1],[2]
Mid-Continent [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	-0.34
Mid-Continent [Member] | Subsequent Event [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount			15,000	[1]
Mid-Continent [Member] | Subsequent Event [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price			-0.27
Permian Basin [Member] | Basis Swap Contracts for Current Year [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	10,000	[1]
Permian Basin [Member] | Basis Swap Contracts for Current Year [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	-0.13
Permian Basin [Member] | Basis Swap Contracts for Year 2 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0	[1]
Permian Basin [Member] | Basis Swap Contracts for Year 2 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0
Permian Basin [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, in MMBTU [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	0	[1]
Permian Basin [Member] | Basis Swap Contracts for Year 3 [Member] | Gas contracts, price per MMBTU [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	0
[1]	(a)Represent swaps that fix the basis differentials between the index prices at which the Company sells its Gulf Coast, Mid-Continent and Permian Basin gas, respectively, and the NYMEX Henry Hub index price used in gas swap and collar contracts.
[2]	(b) During the period from April 1, 2015 through May 5, 2015, the Company entered into additional basis swap contracts for 15,000 MMBtu per day of the Company's 2017 production with a negative price differential of $0.27 per MMBtu between the relevant index price and the NYMEX price.

Derivative_Financial_Instrumen6

Derivative Financial Instruments Derivative Financial Instruments (Schedule of Marketing Derivative Contracts Volume and Weighted Average Prices) (Details) (Details)	Mar. 31, 2015	5-May-15
Marketing Oil contracts, in BBL [Member] | Basis Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	10,000
Marketing oil contracts, price per BBL [Member] [Member] | Basis Swap Contracts for Current Year [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price	2.99
Subsequent Event [Member] | Marketing Oil contracts, in BBL [Member] | Basis Swap Contracts for June 2015 [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		6,000
Subsequent Event [Member] | Marketing oil contracts, price per BBL [Member] [Member] | Basis Swap Contracts for June 2015 [Member]
Derivative [Line Items]
Derivative, Swap Type, Average Fixed Price		5.7

Derivative_Financial_Instrumen7

Derivative Financial Instruments (Schedule Of Derivative Instruments) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Derivative [Line Items]
Derivative Assets, Current	$624	$578
Derivative Assets, Noncurrent	181	181
Derivative Liabilities, Current	16	3
Derivative Liabilities, Noncurrent	0	2
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Net	805	759
Derivative Liability, Fair Value, Net	16	5
Not Designated as Hedging Instrument [Member] | Commodity Price Derivatives [Member] | Derivatives - Current [Member]
Derivative [Line Items]
Total derivatives, Asset, Gross	627	579
Derivative Liability, Fair Value, Gross Liability	6	1
Derivative Assets Offset In Balance Sheet	-3	-1
Derivative Liabilities Offset In Balance Sheet	-3	-1
Derivative Assets, Current	624	578
Derivative Liabilities, Current	3	0
Not Designated as Hedging Instrument [Member] | Commodity Price Derivatives [Member] | Derivatives - Noncurrent [Member]
Derivative [Line Items]
Total derivatives, Asset, Gross	183	182
Derivative Liability, Fair Value, Gross Liability	2	3
Derivative Assets Offset In Balance Sheet	-2	-1
Derivative Liabilities Offset In Balance Sheet	-2	-1
Derivative Assets, Noncurrent	181	181
Derivative Liabilities, Noncurrent	0	2
Not Designated as Hedging Instrument [Member] | Interest Rate Derivatives [Member] | Derivatives - Current [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	13	3
Derivative Liabilities Offset In Balance Sheet	0	0
Derivative Liabilities, Current	$13	$3

Derivative_Financial_Instrumen8

Derivative Financial Instruments (Schedule Of Derivative Obligations Under Terminated Hedge Arrangements) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Derivative [Line Items]
Derivative Liabilities, Current	$16		$3
Derivative gains (losses), net	241	-104
Commodity Price Derivatives [Member] | Derivative Gains (Losses), Net [Member]
Derivative [Line Items]
Derivative gains (losses), net	251	-114
Interest Rate Derivatives [Member] | Derivative Gains (Losses), Net [Member]
Derivative [Line Items]
Derivative gains (losses), net	-10	10
Not Designated as Hedging Instrument [Member] | Derivatives - Current [Member] | Commodity Price Derivatives [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	6		1
Derivative Liabilities Offset In Balance Sheet	-3		-1
Derivative Liabilities, Current	3		0
Not Designated as Hedging Instrument [Member] | Derivatives - Current [Member] | Interest Rate Derivatives [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	13		3
Derivative Liabilities Offset In Balance Sheet	0		0
Derivative Liabilities, Current	$13		$3

Exploratory_Costs_Schedule_Of_

Exploratory Costs (Schedule Of Capitalized Exploratory Well And Project Activity) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Beginning capitalized exploratory costs	$305
Additions to exploratory costs pending the determination of proved reserves	226
Reclassification due to determination of proved reserves	-216
Impairment of oil and gas properties	138	0
Exploratory well costs charged to exploration expense	-5
Ending capitalized exploratory costs	$310
Number of projects with exploratory costs that have been suspended for a period greater than one year	0	0

Exploratory_Costs_Exploratory_

Exploratory Costs Exploratory Costs (Narrative) (Details)	Mar. 31, 2015	Mar. 31, 2014
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Number of projects with exploratory costs that have been suspended for a period greater than one year	0	0

LongTerm_Debt_Details

Long-Term Debt (Details) (USD $)	Mar. 31, 2015
Debt Instrument [Line Items]
Maximum Borrowing Capacity	$1,500,000,000
Outstanding borrowing	$0

Incentive_Plans_Incentive_Plan

Incentive Plans Incentive Plans (Stock-based compensation) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred Compensation Arrangement with Individual, Compensation Expense	$29	$31
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	200
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years 0 months 0 days
Restricted Stock Liability Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	44
Accounts Payable, Current	$6		$23

Incentive_Plans_Incentive_Plan1

Incentive Plans Incentive Plans (Share Based Incentive Award Activity) (Details)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Restricted Stock Equity Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,176,183	1,233,539
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	422,966
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	-476,698
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	-3,624
Restricted Stock Liability Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	318,829	328,087
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	158,726
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	-160,751
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	-7,233
Performance Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	237,164	154,733
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	82,431
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	199,058	199,058
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	0

Asset_Retirement_Obligations_D

Asset Retirement Obligations (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning asset retirement obligations	$189	$194
Asset Retirement Obligation, Liabilities Incurred	1	1
Changes in estimates	0	1
Disposition of wells	0	-1
Liabilities settled	-5	-4
Accretion of discount from continuing operations	3	3
Ending asset retirement obligations	188	194
Asset retirement obligations, current portions	$31		$28

Interest_And_Other_Income_Comp

Interest And Other Income (Components Of Interest And Other Income) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Interest and Other Income [Abstract]
Deferred compensation plan income	$3		$2
Equity interest in income of unconsolidated affiliate	2	[1]	3	[1]
Other income	1		2
Third-party income (loss) from vertical integration services	0	[2]	-2	[2]
Total interest and other income	6		5
GrossRevenuesIncludedInThirdPartyIncomeFromVerticalIntegrationServices	112		92
GrossExpensesIncludedInThirdPartyIncomeFromVerticalIntegrationServices	$112		$94
[1]	(a)The Company accounts for its investment in EFS Midstream LLC ("EFS Midstream") using the equity method. EFS Midstream is providing gathering, treating and transportation services for the Company during a 20-year contractual term.
[2]	(b)Loss from vertical integration services primarily represents net margins that result from Company-provided fracture stimulation and related service operations, which are ancillary to and supportive of the Company's oil and gas joint operating activities, and do not represent intercompany transactions. For the three months ended March 31, 2015, these vertical integration net margins included $112 million of revenues and $112 million of costs and expenses. For the same period in 2014, these vertical integration net margins included $92 million of revenues and $94 million of costs and expenses.

Other_Expense_Schedule_Of_Comp

Other Expense (Schedule Of Components Of Other Expense) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Other Expense [Abstract]
Above market and idle drilling and well services equipment charges	$23	[1]	$0	[1]
Transportation commitment charges	14	[2]	11	[2]
Inventory valuation charges	6	[3]	0	[3]
Other	5		2
Contingency and environmental accrual adjustments	0		2
Total other expense	$48		$15
[1]	Primarily represents expenses attributable to idle drilling rig fees, which are not chargeable to joint operations.
[2]	Primarily represents firm transportation payments on excess pipeline capacity commitments.
[3]	Represents charges to reduce excess material and supplies inventories to their market values. See Note D for additional information on the fair value of materials and supplies inventory.

Income_Taxes_Schedule_Of_Incom

Income Taxes (Schedule Of Income Tax (Provisions) Benefits Attributable To Income From Continuing Operations) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
	Rate	Rate
Income Tax Disclosure [Abstract]
Current income taxes	$0	($12,000,000)
Deferred income taxes	37,000,000	-39,000,000
Income tax benefit (provision)	37,000,000	-51,000,000
Effective Tax Rate	33.00%	26.00%
Statutory Tax Rate	35.00%	35.00%
Unrecognized tax benefit recognized in period		21,000,000
Unrecognized Tax Benefits	$0

Net_Income_Per_Share_Reconcili

Net Income Per Share (Reconciliation Of Earnings Attributable To Common Stockholders, Basic And Diluted) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement Operating Activities Segment [Line Items]
Basic income (loss) from continuing operations attributable to common stockholders	($78)	$122
Diluted income (loss) from continuing operations attributable to common stockholders	-78	122
Continuing Operations [Member]
Statement Operating Activities Segment [Line Items]
Income (loss) from continuing operations attributable to parent	-74	145
Participating Securities, Distributed and Undistributed Earnings, Basic	0	-1
Basic income (loss) from continuing operations attributable to common stockholders	-74	144
Diluted income (loss) from continuing operations attributable to common stockholders	-74	144
Discontinued Operations [Member]
Statement Operating Activities Segment [Line Items]
Basic income (loss) from continuing operations attributable to common stockholders	-4	-22
Diluted income (loss) from continuing operations attributable to common stockholders	($4)	($22)

Net_Income_Per_Share_Reconcili1

Net Income Per Share (Reconciliation Of Basic To Diluted Weighted Average Common Shares Outstanding) (Details)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Weighted Average Number of Shares Outstanding Reconciliation [Line Items]
Basic	149	143
Diluted	149	143

Subsequent_Events_Details

Subsequent Events (Details) (Subsequent Event [Member], USD $)	6-May-15
In Millions, unless otherwise specified	Rate
Efs Midstream [Member]
Subsequent Event [Line Items]
Equity Method Investment, Ownership Percentage	50.10%
Minimum [Member]
Subsequent Event [Line Items]
Restructuring and Related Cost, Expected Cost	15
Maximum [Member]
Subsequent Event [Line Items]
Restructuring and Related Cost, Expected Cost	30