Segment Information (Unaudited) Unallocated Corporate Income (Details 5) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2021	Sep. 30, 2021
Segment Reporting [Abstract]
Pre-tax gain on sale of business	$ 2,000	$ 2,000
Unallowable State Taxes and Transactions Costs from Divestiture	$ 192

Unallowable State Taxes and Transactions Costs from Divestiture

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration