Cost of natural gas purchased and associated transportation and storage costs during the period.

No definition available.

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- Definition

Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25383-109308

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 6

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

Amount of the recorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of the recorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of the recorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of the recorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

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- Definition

Amount of the recorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

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Commitments And Contingencies (Gas Supply, Transportation And Storage) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Long-term Purchase Commitment [Line Items]
2013	$ 3,094
2014	3,434
2015	3,414
2016	3,298
2017	3,140
Thereafter	36,518
Total	52,898
Pacific Gas And Electric Company [Member]
Long-term Purchase Commitment [Line Items]
Cost of natural gas purchases	1,300	1,800	1,600
Natural Gas, Gas Transportation and Gas Storage Purchases [Member]
Long-term Purchase Commitment [Line Items]
2013	707
2014	208
2015	192
2016	152
2017	108
Thereafter	865
Total	$ 2,232