LOANS AND LEASES - Schedule of Loans Charge-offs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	$ 0	$ 1
Year two	22	20
Year three	39	31
Year four	34	17
Year five	11	3
Prior year	25	32
Revolving	35	24
Revolving Converted to Term Loans	1	0
Total	167	128
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	1
Year two	17	10
Year three	23	12
Year four	21	4
Year five	5	2
Prior year	23	32
Revolving	15	14
Revolving Converted to Term Loans	1	0
Total	105	75
Commercial | Non-owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	10	0
Year three	3	0
Year four	10	0
Year five	0	0
Prior year	17	29
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	40	29
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	1
Year two	6	8
Year three	19	8
Year four	10	2
Year five	4	1
Prior year	5	2
Revolving	15	14
Revolving Converted to Term Loans	1	0
Total	60	36
Commercial | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	1	2
Year three	1	4
Year four	1	2
Year five	1	1
Prior year	1	1
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	5	10
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	1	1
Year three	2	2
Year four	1	0
Year five	0	0
Prior year	0	0
Revolving	4	4
Revolving Converted to Term Loans	0	0
Total	8	7
Consumer | Consumer auto
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	1	1
Year three	1	1
Year four	1	0
Year five	0	0
Prior year	0	0
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	3	2
Consumer | Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	0
Year three	1	1
Year four	0	0
Year five	0	0
Prior year	0	0
Revolving	4	4
Revolving Converted to Term Loans	0	0
Total	5	5
SVB
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	4	9
Year three	14	17
Year four	12	13
Year five	6	1
Prior year	2	0
Revolving	16	6
Revolving Converted to Term Loans	0	0
Total	54	46
SVB | Investor dependent - early stage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	4	4
Year three	14	13
Year four	9	6
Year five	3	0
Prior year	0	0
Revolving	1	1
Revolving Converted to Term Loans	0	0
Total	31	24
SVB | Investor dependent - growth stage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	2
Year three	0	4
Year four	3	7
Year five	3	1
Prior year	2	0
Revolving	0	0
Revolving Converted to Term Loans	0	0
Total	8	14
SVB | Innovation C&I and cash flow dependent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Year one	0	0
Year two	0	3
Year three	0	0
Year four	0	0
Year five	0	0
Prior year	0	0
Revolving	15	5
Revolving Converted to Term Loans	0	0
Total	$ 15	$ 8