Investment Securities (Details 3) $ in Millions	Jun. 30, 2021 USD ($)
Cost
Due within 1 year	$ 11,001
Due after 1 year but within 5 years	1,201
Due after 5 years but within 10 years	35
Due after 10 years	99
Total	12,336
Estimated Fair Value
Due within 1 year	11,014
Due after 1 year but within 5 years	1,235
Due after 5 years but within 10 years	42
Due after 10 years	101
Total	$ 12,392

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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