Investment Securities (Details 3) $ in Millions	Sep. 30, 2021 USD ($)
Cost
Due within 1 year	$ 8,453
Due after 1 year but within 5 years	879
Due after 5 years but within 10 years	35
Due after 10 years	75
Total	9,442
Estimated Fair Value
Due within 1 year	8,460
Due after 1 year but within 5 years	909
Due after 5 years but within 10 years	41
Due after 10 years	77
Total	$ 9,487

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