v2.4.0.6

Contingencies and Commitments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Commitments [Line Items]
Letters of credit issued under revolving credit facilities	$ 1,954
Aggregate amounts of estimated payments - 2012	468
Aggregate amounts of estimated payments - 2013	467
Aggregate amounts of estimated payments - 2014	467
Aggregate amounts of estimated payments - 2015	458
Aggregate amounts of estimated payments - 2016	364
Aggregate amounts of estimated payments - 2017 and after	4,890
Total payments under long-term throughput agreements and take-or-pay agreements	429	216	114
Revolving Credit Facility [Member]
Commitments [Line Items]
Letters of credit issued under revolving credit facilities	$ 40

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 4

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the four fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

+ References

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-Publisher FASB

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The amount purchased during the period under an unrecorded unconditional purchase obligation (for example, under the take-or-pay or throughput contract).

+ References

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-Name Accounting Standards Codification

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