Investment Securities (Details 3) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Cost
Due within 1 year	$ 11,483
Due after 1 year but within 5 years	7,946
Due after 5 years but within 10 years	179
Due after 10 years	149
Total	19,757
Estimated Fair Value
Due within 1 year	11,499
Due after 1 year but within 5 years	8,017
Due after 5 years but within 10 years	198
Due after 10 years	155
Total	$ 19,869	$ 8,328

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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