Commitments And Contingencies (Environmental Remediation Contingencies) (Details) (USD $)			3 Months Ended
	Mar. 31, 2012	Oct. 31, 2011	Mar. 31, 2012 Pacific Gas And Electric Company [Member]	Dec. 31, 2011 Pacific Gas And Electric Company [Member]	Mar. 31, 2012 Hinkley Natural Gas Compressor Station [Member]	Dec. 31, 2011 Hinkley Natural Gas Compressor Station [Member]	Mar. 31, 2012 Hinkley Natural Gas Compressor Station [Member] Pacific Gas And Electric Company [Member]
Long-term Purchase Commitment [Line Items]
Requisite parts for permanent water system replacement, in ppb		3.1
Eligible resident households for voluntary program	300
Amount of environmental loss accrual expected to be recovered	$ 50,000,000		$ 427,000,000
Additional environmental recoveries receivable	99,000,000
Authorized recovery of hazardous waste remediation costs							90.00%
Recovery of remediation costs for decommissioning fossil-fueled sites			100.00%
Increase in undiscounted future costs in the event other potentially responsible parties are not able to contribute			1,600,000,000
Utility undiscounted future costs			$ 921,000,000	$ 785,000,000	$ 218,000,000	$ 149,000,000