Basis Of Presentation Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 77		$ 69
Equity in earnings of unconsolidated entities	(9)	$ (1)
Dividends received from unconsolidated entities	1	1
Payments to Acquire Equity Method Investments	1	2
Guaranteed Rate Affinity
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 69		$ 60
Payments to Acquire Equity Method Investments		$ 2

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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