Basis Of Presentation Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Equity in earnings of unconsolidated entities	$ (31)	$ (9)
Dividends received from unconsolidated entities	31	1
Guaranteed Rate Affinity
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	90		$ 90
Equity in earnings of unconsolidated entities	(30)	(9)
Dividends received from unconsolidated entities	30	0
Other Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	12		$ 10
Equity in earnings of unconsolidated entities	(1)	0
Dividends received from unconsolidated entities	$ 1	$ 1

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

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