Investment Securities (Details 3) $ in Millions	Sep. 30, 2019 USD ($)
Cost
Due within 1 year	$ 6,642
Due after 1 year but within 5 years	1,309
Due after 5 years but within 10 years	150
Due after 10 years	218
Total	8,319
Estimated Fair Value
Due within 1 year	6,649
Due after 1 year but within 5 years	1,335
Due after 5 years but within 10 years	157
Due after 10 years	229
Total	$ 8,370

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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