Investment Securities (Details 3) $ in Millions	Jun. 30, 2019 USD ($)
Available For Sale Securities Debt Maturities Amortized Cost [Abstract]
Due within 1 year	$ 6,635
Due after 1 year but within 5 years	1,307
Due after 5 years but within 10 years	190
Due after 10 years	278
Total	8,410
Estimated Fair Value
Estimated Fair Value, Due within 1 year	6,644
Estimated Fair Value, Due after 1 year but within 5 years	1,331
Estimated Fair Value, Due after 5 years but within 10 years	196
Estimated Fair Value, Due after 10 years	286
Total	$ 8,457

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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