Collateralized Agreements and Offsetting Arrangements - Underlying Collateral Pledged (Details) - US Treasury Securities - Asset Pledged as Collateral with Right - Securities Sold under Agreements to Repurchase - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Collateral in the Form of Securities Pledged [Line Items]
Financial Instruments, Owned, at Fair Value	$ 6,459	$ 8,220
Overnight and continuous
Collateral in the Form of Securities Pledged [Line Items]
Financial Instruments, Owned, at Fair Value	0	0
30 days or less
Collateral in the Form of Securities Pledged [Line Items]
Financial Instruments, Owned, at Fair Value	6,459	8,220
After 30 days through 90 days
Collateral in the Form of Securities Pledged [Line Items]
Financial Instruments, Owned, at Fair Value	0	0
Greater than 90 days
Collateral in the Form of Securities Pledged [Line Items]
Financial Instruments, Owned, at Fair Value	$ 0	$ 0