Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

The amount of gain (loss), net of tax, on derivative instruments recognized in other comprehensive (income) loss prior to settlement of interest rate swap.

+ References

No definition available.

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- Definition

Net of tax amount remaining in Accumulated Other Comprehensive Loss that will be reclassified into interest expense over the life of the debt.

+ References

No definition available.

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- Definition

Net of tax amount in Accumulated Other Comprehensive Loss that will be reclassified into interest expense over the life of the debt (original amount).

+ References

No definition available.

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- Definition

Contract period of time relating to a derivative instrument.

+ References

No definition available.

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- Definition

The position of the settled interest rate swap as of the settlement date.

+ References

No definition available.

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The average cap rate on a group of price risk derivatives such as caps or collars. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract.

+ References

No definition available.

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- Definition

The average floor rate on a group of price risk derivatives such as floors or collars. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

+ References

No definition available.

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- Definition

The average strike price on the group of price risk option contracts such as put options or call options.

+ References

No definition available.

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- Definition

Average fixed price related to the group of price risk swap derivatives.

+ References

No definition available.

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- Definition

Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

+ References

No definition available.

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Derivative Instruments and Hedging Activities (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2011	Dec. 31, 2012	Feb. 15, 2011
Derivative Instruments and Hedging Activities [Abstract]
Amount of Gain (Loss) on Derivative Instruments Recognized in Other Comprehensive (Income) Loss	$ 23
Net liability position of settled interest rate swap			40
AOCL amount, net of tax, to be reclassified to interest expense over life of debt		25
AOCL amount, net of tax, to be reclassified to interest expense over life of debt, original amount			26
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months		$ 2
Crude Oil Commodity Contract \| Swaps 3
Derivative [Line Items]
Settlement Period		2013
Index		NYMEX WTI
Volume Per Day		8,000
Weighted Average Fixed Price		89.63
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract \| Swaps 4
Derivative [Line Items]
Settlement Period		2013
Index		Dated Brent
Volume Per Day		3,000
Weighted Average Fixed Price		98.03
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract \| Two Way Collar 1
Derivative [Line Items]
Settlement Period		2013
Index		NYMEX WTI
Volume Per Day		5,000
Weighted Average Fixed Price
Weighted Average Short Put Price
Weighted Average Floor Price		95.00
Weighted Average Ceiling Price		115.00
Crude Oil Commodity Contract \| Three Way Collars 3
Derivative [Line Items]
Settlement Period		2013
Index		NYMEX WTI
Volume Per Day		7,000
Weighted Average Fixed Price
Weighted Average Short Put Price		63.57
Weighted Average Floor Price		83.57
Weighted Average Ceiling Price		109.04
Crude Oil Commodity Contract \| Three Way Collars 4
Derivative [Line Items]
Settlement Period		2013
Index		Dated Brent
Volume Per Day		26,000
Weighted Average Fixed Price
Weighted Average Short Put Price		82.50
Weighted Average Floor Price		100.93
Weighted Average Ceiling Price		126.63
Crude Oil Commodity Contract \| Swaps 5
Derivative [Line Items]
Settlement Period		2014
Index		NYMEX WTI
Volume Per Day		11,000
Weighted Average Fixed Price		90.26
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract \| Swaps 6
Derivative [Line Items]
Settlement Period		2014
Index		Dated Brent
Volume Per Day		10,000
Weighted Average Fixed Price		105.14
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract \| Three Way Collars 6
Derivative [Line Items]
Settlement Period		2014
Index		NYMEX WTI
Volume Per Day		4,000
Weighted Average Fixed Price
Weighted Average Short Put Price		77.00
Weighted Average Floor Price		92.00
Weighted Average Ceiling Price		106.13
Crude Oil Commodity Contract \| Three Way Collars 5
Derivative [Line Items]
Settlement Period		2014
Index		Dated Brent
Volume Per Day		11,000
Weighted Average Fixed Price
Weighted Average Short Put Price		85.45
Weighted Average Floor Price		99.09
Weighted Average Ceiling Price		128.40
Natural Gas Commodity Contract \| Three Way Collars 3
Derivative [Line Items]
Settlement Period		2014
Index		NYMEX HH
Volume Per Day		130,000
Weighted Average Fixed Price
Weighted Average Short Put Price		2.56
Weighted Average Floor Price		3.56
Weighted Average Ceiling Price		5.21
Natural Gas Commodity Contract \| Swaps 2
Derivative [Line Items]
Settlement Period		2013
Index		NYMEX HH
Volume Per Day		60,000
Weighted Average Fixed Price		4.58
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Natural Gas Commodity Contract \| Two Way Collar 2
Derivative [Line Items]
Settlement Period		2013
Index		NYMEX HH
Volume Per Day		40,000
Weighted Average Fixed Price
Weighted Average Short Put Price
Weighted Average Floor Price		3.25
Weighted Average Ceiling Price		5.14
Natural Gas Commodity Contract \| Three Way Collars 2
Derivative [Line Items]
Settlement Period		2013
Index		NYMEX HH
Volume Per Day		100,000
Weighted Average Fixed Price
Weighted Average Short Put Price		3.88
Weighted Average Floor Price		4.75
Weighted Average Ceiling Price		5.63
Natural Gas Commodity Contract \| Swaps 1
Derivative [Line Items]
Settlement Period		2014
Index		NYMEX HH
Volume Per Day		60,000
Weighted Average Fixed Price		4.24
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price