Derivatives And Hedging Activities (Gains And Losses On Derivative Instruments) (Details) - PGE Corporation Utility [Member] - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Unrealized (loss) gain - regulatory assets and liabilities	[1]	$ (71)	$ 64	$ (6)
Realized loss-cost of electricity	[2]	(27)	(53)	(14)
Realized loss-cost of natural gas	[2]	(5)	(18)	(10)
Total commodity risk instruments		$ (103)	$ (7)	$ (30)

[1] Unrealized gains and losses on commodity risk-related derivative instruments are recorded to regulatory assets or liabilities, rather than being recorded to the Consolidated Statements of Income. These amounts exclude the impact of cash collateral postings.

[2] These amounts are fully passed through to customers in rates. Accordingly, net income was not impacted by realized amounts on these instruments.