Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM format.

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Firm transportation capacity assumed, per day.

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Net production per day of acreage sold in MMcf.

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Number of miles of natural gas gathering pipeline.

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Number Of Wells

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Pipeline capacity per day.

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Area of land held.

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The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for assets of a disposal group, including a component of the entity (discontinued operation), to be sold or that has been disposed of through sale, as of the financial statement date.

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Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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Including the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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The cash outflow to purchase of mineral interests in oil and gas properties for use in the normal oil and gas operations and not intended for resale.

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The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

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Acquisitions And Divestitures (Narrative) (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended		3 Months Ended	1 Months Ended	0 Months Ended	1 Months Ended	12 Months Ended	0 Months Ended	6 Months Ended
	Jan. 31, 2015	Dec. 31, 2014	Mar. 31, 2015	Mar. 31, 2015	Dec. 19, 2014	Apr. 22, 2015	Dec. 31, 2014	Dec. 22, 2014	Sep. 30, 2014 acre
Bridge Loan [Member]
Business Acquisition [Line Items]
Term loan, maturity date			2015-12
Bridge loan	$ 4,500	$ 4,500	$ 4,500	$ 4,500			$ 4,500
Debt instrument, term	364 days	364 days	364 days
Debt issuance costs	47
Oil And Gas Assets Located In East Texas And Arkona Basin [Member]
Business Acquisition [Line Items]
Proceeds from sale of oil and gas property and equipment				218
Unsecured Debt [Member] \| Term Loan [Member]
Business Acquisition [Line Items]
Loans payable		500	500	500	500	500	500
Term loan, maturity date						2016-12	2016-12
Debt instrument, term		2 years			2 years
WPX Property Acquisition [Member]
Business Acquisition [Line Items]
Area of land purchased	46,700
Cash consideration	288
Net production per day of acreage sold in MMcf		50					50
Number of horizontal wells operated		63
Firm transportation capacity assumed, per day		260
Allocated to natural gas and oil properties	169
Allocated to intangible assets	119
Statoil Property Acquisition [Member]
Business Acquisition [Line Items]
Area of land purchased	30,000
Allocated to natural gas and oil properties	365
Percentage of interest acquired	20.00%
Cost to acquire property	365
Chesapeake Property Acquisition [Member]
Business Acquisition [Line Items]
Area of land purchased		413,000					413,000
Cash consideration								4,978
Niobrara Formation In Colorado [Member]
Business Acquisition [Line Items]
Area of land purchased									380,000
Cost to acquire property									215
Subsequent Event [Member] \| Gathering Assets Located In Bradford And Lycoming Counties [Member]
Business Acquisition [Line Items]
Proceeds from sale of oil and gas property and equipment						488
Net book value of assets sold						$ 213
Number of miles of natural gas gathering pipeline						100
Pipeline capacity per day						600