INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Amortized Cost
Due within one year	$ 628
Due after one year through five years	2,332
Due after five years through ten years	1,694
Due after ten years	473
Mortgage and asset-backed securities	5,118
Amortized Cost	10,245	$ 10,641
Fair Value
Due within one year	628
Due after one year through five years	2,357
Due after five years through ten years	1,734
Due after ten years	488
Mortgage and asset-backed securities	5,195
Fair Value	$ 10,402	$ 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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