Reserves for Insurance Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross reserves for insurance losses and loss adjustment expenses, beginning balance	$ 119	$ 122	$ 129
Less: Reinsurance recoverable	72	81	90
Net reserves for insurance losses and loss adjustment expenses	74	47	41	$ 39
Current year	414	282	259
Prior years	8	(2)	2
Total net insurance losses and loss adjustment expenses incurred	422	280	261
Current year	(354)	(246)	(229)
Prior years	(41)	(28)	(30)
Total net insurance losses and loss adjustment expenses paid or payable	(395)	(274)	(259)
Plus: Reinsurance recoverable	66	72	81
Gross reserves for insurance losses and loss adjustment expenses, ending balance	$ 140	$ 119	$ 122