Investment Securities (Details 4) $ in Millions	Mar. 31, 2022 USD ($)
Cost
Due within 1 year	$ 1,740
Due after 1 year but within 5 years	2,167
Due after 5 years but within 10 years	35
Due after 10 years	68
Total	4,010
Estimated Fair Value
Due within 1 year	1,745
Due after 1 year but within 5 years	2,155
Due after 5 years but within 10 years	38
Due after 10 years	65
Total	$ 4,003

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