INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Amortized Cost
Due within one year	$ 1,243
Due after one year through five years	5,279
Due after five years through ten years	2,936
Due after ten years	1,149
Mortgage and asset-backed securities	7,695
Amortized Cost	18,302	$ 15,946
Fair Value
Due within one year	1,239
Due after one year through five years	5,112
Due after five years through ten years	2,657
Due after ten years	962
Mortgage and asset-backed securities	7,038
Total debt securities	$ 17,008	$ 14,254

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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-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
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