Subsidiary Debt - HomeServices (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Par value	$ 52,313
Subsidiary debt
Debt Instrument [Line Items]
Par value	39,012
Subsidiary debt	38,971	$ 37,539
HomeServices | Subsidiary debt
Debt Instrument [Line Items]
Par value	133
Subsidiary debt	$ 133	$ 140
HomeServices | Subsidiary debt | Variable-rate term loan (2021 - 0.950%, 2020 - 1.147%), due 2026
Debt Instrument [Line Items]
Stated rate	6.27%	5.242%
Par value	$ 133
Subsidiary debt	$ 133	$ 140