Goodwill and Other Intangible Assets (Goodwill) (Details) $ in Millions	Dec. 31, 2021 USD ($)
Changes in the Carrying Amount of Goodwill by Segment [Roll Forward]
Balance at beginning of period	$ 716
Balance at end of period	716
Kentucky Regulated [Member]
Changes in the Carrying Amount of Goodwill by Segment [Roll Forward]
Balance at beginning of period	662
Balance at end of period	662
Corporate And Other [Member]
Changes in the Carrying Amount of Goodwill by Segment [Roll Forward]
Balance at beginning of period	53
Balance at end of period	$ 53