Derivatives - Derivative Liabilities and Collateral Pledged (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Gross amounts of recognized liabilities	$ 103	$ 125
Gross  amounts offset in the Balance Sheets	0	0
Net amounts of liabilities presented in the Statements of Condition	103	125
Derivative assets available for offset	(36)	(21)
Collateral pledged	(39)	(82)
Net amount	28	22
Derivative liabilities not subject to master netting agreements	24	22
Derivatives, interest rate contracts
Derivative [Line Items]
Gross amounts of recognized liabilities	93	60
Gross  amounts offset in the Balance Sheets	0	0
Net amounts of liabilities presented in the Statements of Condition	93	60
Derivative assets available for offset	(32)	(7)
Collateral pledged	(38)	(31)
Net amount	23	22
Forward contracts
Derivative [Line Items]
Gross amounts of recognized liabilities	10	65
Gross  amounts offset in the Balance Sheets	0	0
Net amounts of liabilities presented in the Statements of Condition	10	65
Derivative assets available for offset	(4)	(14)
Collateral pledged	(1)	(51)
Net amount	$ 5	$ 0