Contingencies, Commitments and Guarantees - Lease Commitments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Lease liability, balance sheet location	Other Liabilities	Other Liabilities
Right of use asset, balance sheet location	Other assets	Other assets
Lease liabilities	$ 856	$ 868
Right of use asset	690	696
Operating Lease, Lease Income, Lease Payments	$ 156	177
Leases, weighted average discount rate	3.24%
Leases, weighted average lease term	9 years 10 months 24 days
Rent expense	$ 150	$ 164	$ 162