Securities Financing Activities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	$ 0	$ 0
Securities borrowed	0	0
Total	0	0
Repurchase agreements	0	0
Total	0	0
Collateral
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	0	0
Securities borrowed	0	0
Total	0	0
Repurchase agreements	(27)	(31)
Total	(27)	(31)
Federal Agency CMOs
Securities Financing Transaction [Line Items]
Assets pledged as collateral	27
Liabilities pledged as collateral	27
Gross Amount Presented in Balance Sheet
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	0	7
Securities borrowed	0	0
Total	0	7
Repurchase agreements	27	38
Total	27	38
Netting Adjustments
Securities Financing Transaction [Line Items]
Reverse repurchase agreements	0	(7)
Securities borrowed	0	0
Total	0	(7)
Repurchase agreements	0	(7)
Total	$ 0	$ (7)