Basis Of Presentation Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Equity in earnings of unconsolidated entities	$ (10)	$ (36)	$ (41)	$ (45)
Dividends received from unconsolidated entities			38	22
Guaranteed Rate Affinity
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	92		92		$ 90
Equity in earnings of unconsolidated entities	(8)	(35)	(38)	(44)
Dividends received from unconsolidated entities			35	20
Other Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	14		14		$ 10
Equity in earnings of unconsolidated entities	$ (2)	$ (1)	(3)	(1)
Dividends received from unconsolidated entities			$ 3	$ 2

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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