ALLOWANCE FOR CREDIT LOSSES - Credit Quality Indicators (Details) - Credit Card Receivable - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Total credit card loans	$ 742	$ 391
% of Total loans	100.00%	100.00%
Below 640
Financing Receivable, Credit Quality Indicator [Line Items]
Total credit card loans	$ 109	$ 64
% of Total loans	15.00%	16.00%
640-690
Financing Receivable, Credit Quality Indicator [Line Items]
Total credit card loans	$ 190	$ 100
% of Total loans	26.00%	26.00%
Greater than 690
Financing Receivable, Credit Quality Indicator [Line Items]
Total credit card loans	$ 443	$ 227
% of Total loans	59.00%	58.00%