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Investment recorded as available for sale asset, shares owned.

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The pre-tax charge against earnings resulting from the write down of long lived assets due to the difference between the carrying value and lower fair value, and related items.

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Value of investment recorded as available for sale asset.

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No definition available.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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-Name Accounting Standards Codification

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Fair value as of the balance sheet date of price risk derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets on the balance sheet.

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Fair value as of the balance sheet date of price risk derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities on the balance sheet.

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Fair Value Measurements (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Fair Value - Other Financial Instruments
Debt carrying value			$ 8,300.0
Carrying value of debt, net of unamortized discount			8,300.0		$ 6,800.0
Asset impairments and related items		$ 471.0	324.0	$ 471.0
Pre-tax impairment of oil and gas properties			310.0
Proved oil and gas assets - domestic
Fair Value - Other Financial Instruments
Pre-tax impairment of oil and gas properties	$ 160.0
Level 1
Assets:
Available for sale investment			$ 432.0		394.0
Fair Value - Other Financial Instruments
Investment recorded as available for sale asset, shares owned			71.5
Level 2
Fair Value - Other Financial Instruments
Debt estimated fair value			$ 68.0
Total Fair Value
Assets:
Available for sale investment			432.0		394.0
Fair Value - Other Financial Instruments
Debt estimated fair value			8,600.0		7,000.0
Recurring \| Level 1
Assets:
Commodity derivatives			139.0		712.0
Liabilities:
Commodity derivatives			130.0		750.0
Recurring \| Level 2
Assets:
Commodity derivatives			35.0		127.0
Liabilities:
Commodity derivatives			162.0		246.0
Recurring \| Netting and Collateral
Assets:
Commodity derivatives			(139.0)		(742.0)
Liabilities:
Commodity derivatives			(127.0)		(756.0)
Recurring \| Total Fair Value
Assets:
Commodity derivatives			35.0		97.0
Liabilities:
Commodity derivatives			$ 165.0		$ 240.0