LOANS AND LEASES - Schedule of Loans Charge-offs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	$ 20	$ 71
Year two	113	169
Year three	194	103
Year four	56	72
Year five	47	83
Prior year	124	40
Revolving	101	99
Revolving Converted to Term Loans	2	1
Total	657	638	$ 146
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	19	33
Year two	52	100
Year three	88	47
Year four	26	56
Year five	44	83
Prior year	114	38
Revolving	63	56
Revolving Converted to Term Loans	1	1
Total	407	414	126
Commercial | Owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior year	12	0
Revolving	0	1
Revolving Converted to Term Loans	0	0
Total	12	1
Commercial | Non-owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	36	66
Prior year	81	21
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	117	87
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	17	31
Year two	46	90
Year three	81	40
Year four	19	53
Year five	5	15
Prior year	17	16
Revolving	63	55
Revolving Converted to Term Loans	1	1
Total	249	301
Commercial | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	2	2
Year two	6	10
Year three	7	7
Year four	7	3
Year five	3	2
Prior year	4	1
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	29	25
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1	8
Year two	4	2
Year three	3	2
Year four	2	1
Year five	0	0
Prior year	2	2
Revolving	17	13
Revolving Converted to Term Loans	1	0
Total	30	28	20
Consumer | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior year	1	2
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	1	2
Consumer | Revolving mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior year	0
Revolving	0
Revolving Converted to Term Loans	1
Total	1
Consumer | Consumer auto
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	1	1
Year two	2	1
Year three	2	1
Year four	1	1
Year five	0	0
Prior year	0	0
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	6	4
Consumer | Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	7
Year two	2	1
Year three	1	1
Year four	1	0
Year five	0	0
Prior year	1	0
Revolving	17	13
Revolving Converted to Term Loans	0	0
Total	22	22
SVB
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	30
Year two	57	67
Year three	103	54
Year four	28	15
Year five	3	0
Prior year	8	0
Revolving	21	30
Revolving Converted to Term Loans	0	0
Total	220	196	$ 0
SVB | Investor dependent - early stage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	2
Year two	41	30
Year three	66	29
Year four	18	3
Year five	2	0
Prior year	0	0
Revolving	7	11
Revolving Converted to Term Loans	0	0
Total	134	75
SVB | Investor dependent - growth stage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	22
Year two	14	37
Year three	37	25
Year four	10	12
Year five	1	0
Prior year	6	0
Revolving	2	1
Revolving Converted to Term Loans	0	0
Total	70	97
SVB | Innovation C&I and cash flow dependent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	6
Year two	2	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior year	2	0
Revolving	12	18
Revolving Converted to Term Loans	0	0
Total	$ 16	$ 24