Commitments And Contingencies (Natural Gas Supply, Transportation And Storage Commitments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Long-term Purchase Commitment [Line Items]
2012	$ 1,810
2013	2,860
2014	3,010
2015	3,007
2016	2,917
Thereafter	32,120
Total	45,724
Pacific Gas And Electric Company [Member]
Long-term Purchase Commitment [Line Items]
Cost of natural gas purchases	378	433
Natural Gas, Gas Transportation and Gas Storage Purchases [Member]
Long-term Purchase Commitment [Line Items]
2012	475
2013	331
2014	196
2015	187
2016	153
Thereafter	974
Total	$ 2,316

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

No definition available.

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- Definition

The carrying amount of the long-term purchase obligation as of the balance sheet date, which equals the sum of all payments due.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

Reference 3: 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25287-109308

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- Definition

The aggregate remaining amount of payments due after the fifth year after the balance sheet date to extinguish a recorded unconditional purchase obligation.

+ References

Reference 1: 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 2: 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

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- Definition

The aggregate amount of payments due in the fifth year after the balance sheet date to reduce a recorded unconditional purchase obligation.

+ References

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The aggregate amount of payments due in the fourth year after the balance sheet date to reduce a recorded unconditional purchase obligation.

+ References

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- Definition

The aggregate amount of payments due in the second year after the balance sheet date to reduce a recorded unconditional purchase obligation.

+ References

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- Definition

The aggregate amount of payments due in the third year after the balance sheet date to reduce a recorded unconditional purchase obligation.

+ References

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- Definition

The aggregate amount of payments due in the first year after the balance sheet date to reduce a recorded unconditional purchase obligation.

+ References

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