INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Amortized Cost
Due within one year	$ 659
Due after one year through five years	4,850
Due after five years through ten years	3,017
Due after ten years	1,229
Mortgage and asset-backed securities	7,711
Amortized Cost	17,466	$ 15,946
Fair Value
Due within one year	654
Due after one year through five years	4,565
Due after five years through ten years	2,573
Due after ten years	954
Mortgage and asset-backed securities	6,769
Fair Value	$ 15,515	$ 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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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