Reserves for Insurance Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Total gross reserves for insurance losses and loss adjustment expenses, beginning balance			$ 189	$ 140
Less: Reinsurance recoverable			60	66
Net reserves for insurance losses and loss adjustment expenses	$ 188	$ 104	188	104	$ 129	$ 74
Current year			359	281
Prior years			5	12
Total net insurance losses and loss adjustment expenses incurred	203	181	364	293
Current year			(234)	(207)
Prior years			(71)	(56)
Total net insurance losses and loss adjustment expenses paid or payable			(305)	(263)
Plus: Reinsurance recoverable	66	99	66	99
Total gross reserves for insurance losses and loss adjustment expenses, ending balance	$ 254	$ 203	$ 254	$ 203