Property Plant and Equipment Property Plant and Equipment (Details) - USD ($) $ in Millions		Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment		$ 10,109	$ 9,691
Accumulated Depreciation		(2,271)	(2,088)
Property, plant and equipment, net		7,838	7,603
Electric plant
Property, Plant and Equipment [Line Items]
Property, plant and equipment		9,639	9,229
Plant to be Retired [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	[1]	299	316
CWIP
Property, Plant and Equipment [Line Items]
Property, plant and equipment		$ 171	$ 146

[1] Includes expected retirement of Tolk and conversion of Harrington to natural gas.