INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost
Due within one year	$ 437
Due after one year through five years	2,297
Due after five years through ten years	3,077
Due after ten years	1,274
Mortgage and asset-backed securities	6,955
Amortized Cost	14,040	$ 13,440
Fair Value
Due within one year	438
Due after one year through five years	2,240
Due after five years through ten years	2,849
Due after ten years	1,175
Mortgage and asset-backed securities	6,598
Fair Value	$ 13,300	$ 13,497

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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