Basis Of Presentation Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 55		$ 74
Proceeds from investments in unconsolidated entities	19	$ 0
Equity losses from equity method investment	4	3
Dividends received from unconsolidated entities	1	1
Payments to Acquire Equity Method Investments	4	$ 3
Amortization of Intangible Assets related to GRA Acquisition
Schedule of Equity Method Investments [Line Items]
Equity losses from equity method investment	2
PHH Home Loans
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments			19
Guaranteed Rate Affinity
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 47		$ 48

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-03(12))
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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.

+ References

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Dividends received on equity and other investments during the current period.

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

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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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No definition available.

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