Definitive Purchase Agreement to Acquire Natural Gas Properties

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Firm Transportation Capacity Acquired

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Net production per day of acreage sold in MMcf.

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Number Of Wells

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Area of land held.

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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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Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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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 recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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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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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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Amount of the cost of borrowed funds accounted for as interest expense.

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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 net result for the period of deducting operating expenses from operating revenues.

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Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal 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 outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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Acquisitions (Narrative) (Details) (USD $)	3 Months Ended								12 Months Ended			1 Months Ended			0 Months Ended
Acquisitions (Narrative) (Details) (USD $)	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013 acre	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013 acre	Dec. 31, 2012	Dec. 31, 2014 acre	Apr. 30, 2013	Jan. 31, 2015	Jan. 23, 2015	Dec. 19, 2014
Business Acquisition [Line Items]
Area of land purchased					26us-gaap_AreaOfLand					26us-gaap_AreaOfLand
General and administrative expenses									$ 221,000,000	$ 191,000,000	$ 175,000,000
Interest expense									59,000,000us-gaap_InterestExpense	42,000,000us-gaap_InterestExpense	35,000,000us-gaap_InterestExpense
Other current assets	158,000,000us-gaap_OtherAssetsCurrent				48,000,000us-gaap_OtherAssetsCurrent				158,000,000us-gaap_OtherAssetsCurrent	48,000,000us-gaap_OtherAssetsCurrent		158,000,000us-gaap_OtherAssetsCurrent
Revenues	962,000,000us-gaap_Revenues	928,000,000us-gaap_Revenues	1,035,000,000us-gaap_Revenues	1,113,000,000us-gaap_Revenues	907,000,000us-gaap_Revenues	868,000,000us-gaap_Revenues	862,000,000us-gaap_Revenues	734,000,000us-gaap_Revenues	4,038,000,000us-gaap_Revenues	3,371,000,000us-gaap_Revenues	2,730,000,000us-gaap_Revenues
Operating income (loss)	285,000,000us-gaap_OperatingIncomeLoss	286,000,000us-gaap_OperatingIncomeLoss	367,000,000us-gaap_OperatingIncomeLoss	435,000,000us-gaap_OperatingIncomeLoss	317,000,000us-gaap_OperatingIncomeLoss	309,000,000us-gaap_OperatingIncomeLoss	325,000,000us-gaap_OperatingIncomeLoss	252,000,000us-gaap_OperatingIncomeLoss	1,373,000,000us-gaap_OperatingIncomeLoss	1,204,000,000us-gaap_OperatingIncomeLoss	(1,101,000,000)us-gaap_OperatingIncomeLoss
Cost to acquire property									5,298,000,000	96,000,000
Bridge Loan [Member]
Business Acquisition [Line Items]
Bridge loan	4,500,000,000								4,500,000,000			4,500,000,000				4,500,000,000
Debt instrument, term									364 days
Unsecured Debt [Member] \| Term Loan [Member]
Business Acquisition [Line Items]
Loans payable	500,000,000								500,000,000			500,000,000				500,000,000
Debt instrument, term									2 years
Chesapeake Property Acquisition [Member]
Business Acquisition [Line Items]
Date of acquisition									Dec. 22, 2014
Area of land purchased	413,000								413,000			413,000
Cash consideration									4,978,000,000
Assets acquired and liabilities assumed estimated fair value	4,978,000,000								4,978,000,000			4,978,000,000
General and administrative expenses									1,000,000
Interest expense									5,000,000
Other current assets	47,000,000								47,000,000			47,000,000
Unamortized fees	1,000,000								1,000,000			1,000,000
Revenues									10,000,000
Operating income (loss)									2,000,000
Statoil Property Acquisition [Member]
Business Acquisition [Line Items]
Area of land purchased	30,000								30,000			30,000
Percentage of interest acquired	20.00%								20.00%			20.00%
Cost to acquire property												365,000,000
WPX Property Acquisition [Member]
Business Acquisition [Line Items]
Area of land purchased	46,700								46,700			46,700
Cost to acquire property									300,000,000
Net production per day of acreage sold in MMcf	50								50			50
Number of horizontal wells operated by SEECO in Arkansas									63
Firm transportation capacity acquired	260								260			260
Niobrara Formation In Colorado [Member]
Business Acquisition [Line Items]
Area of land purchased	380,000								380,000			380,000
Cost to acquire natural gas properties through definitive purchase agreement									215,000,000
Marcellus Shale In Pennsylvania [Member]
Business Acquisition [Line Items]
Cost to acquire natural gas properties through definitive purchase agreement													82,000,000
Subsequent Event [Member]
Business Acquisition [Line Items]
Debt issuance expense														47,000,000
Subsequent Event [Member] \| Bridge Loan [Member]
Business Acquisition [Line Items]
Repayment of debt														$ 4,500,000,000	$ 4,500,000,000