Investment Securities (Details 3) $ in Millions	Mar. 31, 2021 USD ($)
Cost
Due within 1 year	$ 19,792
Due after 1 year but within 5 years	1,208
Due after 5 years but within 10 years	36
Due after 10 years	114
Total	21,150
Estimated Fair Value
Due within 1 year	19,815
Due after 1 year but within 5 years	1,247
Due after 5 years but within 10 years	42
Due after 10 years	116
Total	$ 21,220

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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