LOANS AND LEASES - Loan Delinquency, including Nonaccrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	$ 115,231	$ 94,378
Current	13,379,610	13,329,692
Gross loans and leases, excluding accrued interest	13,494,841	13,424,070
> 90 days past due and still accruing	1,366	411
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	26,479	25,498
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	19,562	12,104
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	69,190	56,776
Commercial
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	26,431	14,899
Current	4,667,355	4,617,342
Gross loans and leases, excluding accrued interest	4,693,786	4,632,241
> 90 days past due and still accruing	552	0
Commercial \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	13,298	7,894
Commercial \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	2,709	3,176
Commercial \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	10,424	3,829
Lease financing
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	10,926	6,255
Current	638,719	632,272
Gross loans and leases, excluding accrued interest	649,645	638,527
> 90 days past due and still accruing	316	0
Lease financing \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	733	1,884
Lease financing \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	5,457	283
Lease financing \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	4,736	4,088
Construction real estate
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	0	1,120
Current	591,080	676,219
Gross loans and leases, excluding accrued interest	591,080	677,339
> 90 days past due and still accruing	0	0
Construction real estate \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	0	0
Construction real estate \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	0	0
Construction real estate \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	0	1,120
Commercial real estate - investor
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	41,599	43,426
Current	3,276,702	3,203,463
Gross loans and leases, excluding accrued interest	3,318,301	3,246,889
> 90 days past due and still accruing	0	0
Commercial real estate - investor \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	546	3,540
Commercial real estate - investor \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	0	3,613
Commercial real estate - investor \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	41,053	36,273
Commercial real estate-owner
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	16,944	7,502
Current	1,138,223	1,130,165
Gross loans and leases, excluding accrued interest	1,155,167	1,137,667
> 90 days past due and still accruing	0	0
Commercial real estate-owner \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	3,699	1,081
Commercial real estate-owner \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	7,779	2,985
Commercial real estate-owner \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	5,466	3,436
Residential real estate
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	8,512	12,561
Current	1,822,826	1,819,623
Gross loans and leases, excluding accrued interest	1,831,338	1,832,184
> 90 days past due and still accruing	0	0
Residential real estate \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	3,068	6,338
Residential real estate \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	1,154	248
Residential real estate \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	4,290	5,975
Home equity
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	6,978	5,255
Current	1,019,861	999,949
Gross loans and leases, excluding accrued interest	1,026,839	1,005,204
> 90 days past due and still accruing	0	0
Home equity \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	3,209	2,966
Home equity \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	1,600	1,065
Home equity \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	2,169	1,224
Installment
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	2,397	1,881
Current	159,917	186,813
Gross loans and leases, excluding accrued interest	162,314	188,694
> 90 days past due and still accruing	0	65
Installment \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	1,351	935
Installment \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	494	462
Installment \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	552	484
Credit card
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	1,444	1,479
Current	64,927	63,846
Gross loans and leases, excluding accrued interest	66,371	65,325
> 90 days past due and still accruing	498	346
Credit card \| Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	575	860
Credit card \| Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	369	272
Credit card \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss, Noncurrent	$ 500	$ 347

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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