Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (99)	$ (67)
Currency translation adjustment	1	1
Defined benefit pension plan - amortization of actuarial loss to periodic pension cost	1	1
Other comprehensive income, before tax	2	2
Income tax expense (benefit) related to items of other comprehensive income amounts	0	0
Other comprehensive income, net of tax	2	2
Comprehensive loss	(97)	(65)
Less: comprehensive income attributable to noncontrolling interests	0	0
Comprehensive loss attributable to Realogy Holdings and Realogy Group	$ (97)	$ (65)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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