INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Amortized Cost
Due within one year	$ 1,316
Due after one year through five years	1,974
Due after five years through ten years	1,724
Due after ten years	639
Mortgage and asset-backed securities	5,507
Amortized Cost	11,160	$ 10,641
Fair Value
Due within one year	1,317
Due after one year through five years	2,013
Due after five years through ten years	1,780
Due after ten years	654
Mortgage and asset-backed securities	5,607
Fair Value	$ 11,371	$ 10,437

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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