Debt (Details) (USD $)	3 Months Ended					3 Months Ended
	Mar. 31, 2012	Apr. 16, 2012 Utility [Member]	Apr. 02, 2012 Utility [Member]	Mar. 31, 2012 Utility [Member]	Mar. 31, 2012 PGE Corporation And Utility [Member]	Mar. 31, 2012 Floating Rate Senior Notes [Member]	Mar. 31, 2012 Pollution Control Bonds Series 1996 C, E, F, And 1997 B [Member]	Mar. 31, 2012 Pollution Control Bonds Series 1996 C, E, F, And 1997 B [Member] Minimum [Member]	Mar. 31, 2012 Pollution Control Bonds Series 1996 C, E, F, And 1997 B [Member] Maximum [Member]	Mar. 31, 2012 Pollution Control Bonds Series 2009 A-D [Member]	Mar. 31, 2012 Pollution Control Bonds Series 2009 A-D [Member] Minimum [Member]	Mar. 31, 2012 Pollution Control Bonds Series 2009 A-D [Member] Maximum [Member]	Mar. 31, 2012 Energy Recovery Bonds [Member]	Dec. 31, 2005 Energy Recovery Bonds [Member]
Debt [Line Items]
Line of credit facility, maximum borrowing capacity				$ 3,000,000,000	$ 300,000,000
Letters of credit outstanding				367,000,000
Senior Notes		400,000,000
Debt instrument, face amount						250,000,000	614,000,000			309,000,000
Debt instrument, interest rate		4.45%						0.19%	0.22%		0.12%	0.17%
Senior notes maturity period	April 15, 2042					November 20, 2012
Repurchase of principal amount			50,000,000
Commercial paper outstanding				1,100,000,000
Interest rate for the Floating Rate Senior Notes						0.94%
Energy Recovery Bonds issued to refinance a regulatory asset														2,700,000,000
ERB, principal outstanding													$ 321,000,000