Fair Values (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Investment securities:
Equity securities	$ 51	$ 81
Debt securities	12,392
Fair Value, Recurring
Investment securities:
Equity securities	51	81
Debt securities	12,392	21,550
Derivatives, gross	581	629
Total Assets	13,024	22,260
Liabilities
Derivatives, gross	194	702
Total Liabilities	194	702
Level 1 \| Fair Value, Recurring
Investment securities:
Equity securities	50	80
Debt securities	0	0
Derivatives, gross	0	0
Total Assets	50	80
Liabilities
Derivatives, gross	0	0
Total Liabilities	0	0
Level 2 \| Fair Value, Recurring
Investment securities:
Equity securities	1	1
Debt securities	12,372	21,550
Derivatives, gross	581	629
Total Assets	12,954	22,180
Liabilities
Derivatives, gross	194	702
Total Liabilities	194	702
Level 3 \| Fair Value, Recurring
Investment securities:
Equity securities	0	0
Debt securities	20	0
Derivatives, gross	0	0
Total Assets	20	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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