Fair Values (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Investment securities:
Equity securities	$ 102	$ 81
Debt securities	9,487
Fair Value, Recurring
Investment securities:
Equity securities	102	81
Debt securities	9,487	21,550
Derivatives, gross	531	629
Total Assets	10,120	22,260
Liabilities
Derivatives, gross	119	702
Total Liabilities	119	702
Level 1 \| Fair Value, Recurring
Investment securities:
Equity securities	101	80
Debt securities	0	0
Derivatives, gross	0	0
Total Assets	101	80
Liabilities
Derivatives, gross	0	0
Total Liabilities	0	0
Level 2 \| Fair Value, Recurring
Investment securities:
Equity securities	1	1
Debt securities	9,462	21,550
Derivatives, gross	531	629
Total Assets	9,994	22,180
Liabilities
Derivatives, gross	119	702
Total Liabilities	119	702
Level 3 \| Fair Value, Recurring
Investment securities:
Equity securities	0	0
Debt securities	25	0
Derivatives, gross	0	0
Total Assets	25	0
Liabilities
Derivatives, gross	0	0
Total Liabilities	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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