Investment Securities (Details 3) $ in Millions	Mar. 31, 2020 USD ($)
Cost
Due within 1 year	$ 2,703
Due after 1 year but within 5 years	1,798
Due after 5 years but within 10 years	161
Due after 10 years	176
Total	4,838
Estimated Fair Value
Due within 1 year	2,725
Due after 1 year but within 5 years	1,868
Due after 5 years but within 10 years	177
Due after 10 years	187
Total	$ 4,957

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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