INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Amortized Cost
Due within one year	$ 1,487
Due after one year through five years	2,176
Due after five years through ten years	1,999
Due after ten years	1,171
Mortgage and asset-backed securities	5,809
Amortized Cost	12,642	$ 11,160
Fair Value
Due within one year	1,490
Due after one year through five years	2,259
Due after five years through ten years	2,128
Due after ten years	1,210
Mortgage and asset-backed securities	6,046
Fair Value	$ 13,133	$ 11,371

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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