Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

Name:	us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Commitments And Contingencies (Nuclear Fuel Storage) (Details) (USD $) In Millions, unless otherwise specified		96 Months Ended
	Mar. 31, 2012	Dec. 31, 2012 Pacific Gas And Electric Company [Member]	Aug. 03, 2010 Pacific Gas And Electric Company [Member]	Mar. 30, 2010 Pacific Gas And Electric Company [Member]	Dec. 31, 2004 Pacific Gas And Electric Company [Member]
Primary remaining exposure relating to potential environmental obligations of former subsidiary	$ 150
Costs incurred that the Utility sought recovery					92
Amount of costs awarded by U.S. Court of Federal Claims				89
Number of complaints filed			2
Costs incurred to build on-site spent nuclear fuel storage facilities		$ 205