INVESTMENT SECURITIES - Contractual Maturities of Debt Securities Available for Sale (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Amortized Cost
Due within one year	$ 1,390
Due after one year through five years	5,291
Due after five years through ten years	3,791
Due after ten years	1,175
Mortgage and asset-backed securities	7,620
Amortized Cost	19,267	$ 18,302
Fair Value
Due within one year	1,381
Due after one year through five years	5,085
Due after five years through ten years	3,476
Due after ten years	970
Mortgage and asset-backed securities	6,900
Fair Value	$ 17,812	$ 17,008

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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