Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (185)	$ 140	$ 434
Currency translation adjustment	0	(3)	3
Defined Benefit Plans:
Actuarial loss for the plans	(8)	(6)	(1)
Less: amortization of actuarial loss to periodic pension cost	(2)	(2)	(2)
Defined benefit plans	(6)	(4)	1
Other comprehensive (loss) income, before tax	(6)	(7)	4
Income tax (benefit) expense related to items of other comprehensive income (loss)	(2)	(1)	1
Other comprehensive (loss) income, net of tax	(4)	(6)	3
Comprehensive (loss) income	(189)	134	437
Less: comprehensive income attributable to noncontrolling interests	(3)	(3)	(3)
Comprehensive (loss) income attributable to Realogy Holdings and Realogy Group	$ (192)	$ 131	$ 434

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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