Investment Securities (Details 3) $ in Millions	Mar. 31, 2023 USD ($)
Cost
Due within 1 year	$ 2,727
Due after 1 year but within 5 years	1,155
Due after 5 years but within 10 years	41
Due after 10 years	58
Total	3,981
Estimated Fair Value
Due within 1 year	2,694
Due after 1 year but within 5 years	1,137
Due after 5 years but within 10 years	41
Due after 10 years	50
Total	$ 3,922

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