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	$ 4,138	$ 3,880
Accumulated Depreciation	1,478	1,396
Property, Plant and Equipment, Net	2,660	2,484
Electric plant
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	3,348	3,197
Natural gas plant
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	423	391
Common and other property
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	233	221
CWIP
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	$ 134	$ 71

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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