Debt - Schedule of Short-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Short-term Debt [Line Items]
Federal Home Loan Bank	$ 2,925	$ 1,625
Securities sold under agreements to repurchase	931	0
Total short-term borrowings	3,856	1,625
Cash collateral received	2
Unsecured debt
Short-term Debt [Line Items]
Federal Home Loan Bank	0	0
Securities sold under agreements to repurchase	0	0
Total short-term borrowings	0	0
Secured debt
Short-term Debt [Line Items]
Federal Home Loan Bank	2,925	1,625
Securities sold under agreements to repurchase	931	0
Total short-term borrowings	$ 3,856	$ 1,625