Derivatives - Derivative Assets and Collateral Received (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Gross amounts of recognized assets	$ 639	$ 576
Gross amounts offset in the Balance Sheets	0	0
Net amounts of assets presented in the Balance Sheets	639	576
Derivative liabilities available for offset	(82)	(79)
Collateral received	(533)	(489)
Net amount	24	8
Derivative assets not subject to master netting agreements	1	1
Interest rate derivative contracts
Derivative [Line Items]
Gross amounts of recognized assets	633	567
Gross amounts offset in the Balance Sheets	0	0
Net amounts of assets presented in the Balance Sheets	633	567
Derivative liabilities available for offset	(79)	(75)
Collateral received	(533)	(486)
Net amount	21	6
Forward contracts
Derivative [Line Items]
Gross amounts of recognized assets	6	9
Gross amounts offset in the Balance Sheets	0	0
Net amounts of assets presented in the Balance Sheets	6	9
Derivative liabilities available for offset	(3)	(4)
Collateral received	0	(3)
Net amount	$ 3	$ 2