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Net book value of impaired assets

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Value of investment recorded as available for sale asset.

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This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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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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-Publisher FASB
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No definition available.

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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 ($) $ in Millions	3 Months Ended	12 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Millions	Mar. 31, 2015	Dec. 31, 2015	Mar. 31, 2016
Fair value of assets and liabilities measured on recurring basis
Unrealized losses recorded in accumulated other comprehensive income	$ (150.0)
Fair Value - Other Financial Instruments
Carrying value of debt, net of unamortized discount		$ 8,300.0	$ 7,600.0
Midstream
Fair Value - Other Financial Instruments
Net book value of impaired assets		891.0
Pre-tax impairment charges		841.0
Impaired proved oil and gas assets - domestic
Fair Value - Other Financial Instruments
Net book value of impaired assets		7,359.0
Pre-tax impairment charges		4,693.0
Impaired proved oil and gas assets - international
Fair Value - Other Financial Instruments
Net book value of impaired assets		1,655.0
Pre-tax impairment charges		1,030.0
Property, plant, and equipment \| Chemical
Fair Value - Other Financial Instruments
Net book value of impaired assets		124.0
Pre-tax impairment charges		121.0
Level 1
Assets:
Available for sale investment		167.0
Level 2
Fair Value - Other Financial Instruments
Debt estimated fair value			97.0
Level 3 \| Midstream
Fair Value - Other Financial Instruments
Assets, Fair value, nonrecurring		50.0
Level 3 \| Impaired proved oil and gas assets - domestic
Fair Value - Other Financial Instruments
Assets, Fair value, nonrecurring		2,666.0
Level 3 \| Impaired proved oil and gas assets - international
Fair Value - Other Financial Instruments
Assets, Fair value, nonrecurring		625.0
Level 3 \| Property, plant, and equipment \| Chemical
Fair Value - Other Financial Instruments
Assets, Fair value, nonrecurring		3.0
Total Fair Value
Assets:
Available for sale investment		167.0
Fair Value - Other Financial Instruments
Debt estimated fair value		8,400.0	7,900.0
Recurring \| Level 1
Assets:
Commodity derivatives		557.0	492.0
Liabilities:
Commodity derivatives		544.0	525.0
Recurring \| Level 2
Assets:
Commodity derivatives		87.0	51.0
Liabilities:
Commodity derivatives		404.0	386.0
Recurring \| Netting and Collateral
Assets:
Commodity derivatives		(535.0)	(498.0)
Liabilities:
Commodity derivatives		(525.0)	(527.0)
Recurring \| Total Fair Value
Assets:
Commodity derivatives		109.0	45.0
Liabilities:
Commodity derivatives		$ 423.0	$ 384.0
Non recurring \| Low end of range
Fair Value - Other Financial Instruments
Risk adjusted discount rate		8.00%
Non recurring \| High end of range
Fair Value - Other Financial Instruments
Risk adjusted discount rate		20.00%