Derivative Financial Instruments and Off-balance sheet Financial Instruments - Gross and net amounts for OTC derivatives (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Asset derivatives
Gross amount	$ 77	$ 218
Counter- party netting	(1)	(12)
Net amount on balance sheet	76	206
Liability derivatives
Gross amount	(14)	(657)
Counter- party netting	23	2
Net amount on balance sheet	9	(655)
OTC derivatives
Asset derivatives
Gross amount	23	10
Counter- party netting	(24)	(9)
Cash collateral (received) pledged	2	0
Net amount on balance sheet	1	1
Securities collateral (received) pledged	0	0
Net amount	1	1
Liability derivatives
Gross amount	(10)	(19)
Counter- party netting	24	9
Cash collateral (received) pledged	(17)	9
Net amount on balance sheet	(3)	(1)
Securities collateral (received) pledged	0	0
Net amount	$ (3)	$ (1)

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