Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (69)	$ 104	$ (98)	$ 161
Currency translation adjustment	(1)	0	(1)	(2)
Defined benefit pension plan—amortization of actuarial loss to periodic pension cost	1	0	2	1
Other comprehensive income (loss), before tax	0	0	1	(1)
Income tax expense related to items of other comprehensive income amounts	1	0	1	0
Other comprehensive loss, net of tax	(1)	0	0	(1)
Comprehensive (loss) income	(70)	104	(98)	160
Less: comprehensive income attributable to noncontrolling interests	(1)	(1)	(2)	(2)
Comprehensive (loss) income attributable to Realogy Holdings and Realogy Group	$ (71)	$ 103	$ (100)	$ 158

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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