INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Amortized Cost
Due within one year	$ 459
Due after one year through five years	2,200
Due after five years through ten years	3,043
Due after ten years	1,360
Mortgage and asset-backed securities	6,378
Amortized Cost	13,440	$ 12,437
Fair Value
Due within one year	461
Due after one year through five years	2,251
Due after five years through ten years	3,057
Due after ten years	1,374
Mortgage and asset-backed securities	6,354
Fair Value	$ 13,497	$ 12,951

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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