LOANS - Corporate Loans Gross Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 2,926	$ 2,690
Corporate loans
Financing Receivable, Credit Quality Indicator [Line Items]
Current year	1	1
Prior year	2	37
Two years prior	133	9
Three years prior	0	0
Four years prior	0	0
Prior	9	33
Revolving line of credit arrangement	54	98
Total	199	178
Corporate loans | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Current year	0	0
Prior year	2	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	0	0
Revolving line of credit arrangement	46	76
Total	48	76
Corporate loans | Financial institutions
Financing Receivable, Credit Quality Indicator [Line Items]
Current year	0	0
Prior year	0	0
Two years prior	0	0
Three years prior	0	0
Four years prior	0	0
Prior	0	1
Revolving line of credit arrangement	1	7
Total	1	8
Corporate loans | Mortgage and real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Current year	0	1
Prior year	0	37
Two years prior	0	9
Three years prior	0	0
Four years prior	0	0
Prior	6	17
Revolving line of credit arrangement	0	0
Total	6	64
Corporate loans | Other
Financing Receivable, Credit Quality Indicator [Line Items]
Current year	1	0
Prior year	0	0
Two years prior	133	0
Three years prior	0	0
Four years prior	0	0
Prior	3	15
Revolving line of credit arrangement	7	15
Total	$ 144	$ 30