Derivatives - Derivative Assets and Collateral Received (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Gross amounts of recognized assets	$ 437	$ 576
Gross amounts offset in the Balance Sheets	0	0
Net amounts of assets presented in the Balance Sheets	437	576
Derivative liabilities available for offset	(104)	(79)
Collateral received	(296)	(489)
Net amount	37	8
Derivative assets not subject to master netting agreements	1	1
Interest rate derivative contracts
Derivative [Line Items]
Gross amounts of recognized assets	431	567
Gross amounts offset in the Balance Sheets	0	0
Net amounts of assets presented in the Balance Sheets	431	567
Derivative liabilities available for offset	(102)	(75)
Collateral received	(295)	(486)
Net amount	34	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	(2)	(4)
Collateral received	(1)	(3)
Net amount	$ 3	$ 2