New And Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Public Utility, Property, Plant and Equipment [Line Items]
Total nuclear decommissioning asset retirement obligation	$ 3,400,000		$ 3,500,000
Reduction to ARO	66,000
Decrease to cash flow from financing activities	(101,000)	$ (17,000)
2015 NDCTP Adopted Amounts	3,500,000
2015 NDCTP Requested Amounts	4,800,000
Diablo Canyon [Member]
Public Utility, Property, Plant and Equipment [Line Items]
2015 NDCTP Adopted Amounts	2,400,000
2015 NDCTP Requested Amounts	$ 3,800,000
Percentage Of Decommissioning Cost Estimate Approved	64.00%
Humboldt Bay Unit [Member]
Public Utility, Property, Plant and Equipment [Line Items]
2015 NDCTP Adopted Amounts	$ 1,100,000
Pacific Gas And Electric Company [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Decrease to cash flow from financing activities	$ (91,000)	(7,000)
New Accounting Pronouncement [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Decrease to cash flow from financing activities		$ 35,000