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PORTFOLIO LOANS - Schedule of Loan Modifications for Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Term Extension, Interest Rate Reduction And Payment Deferral
Financing Receivable, Modified [Line Items]
% of total class of financing receivable	0.20%		0.40%
Term Extension, Interest Rate Reduction And Payment Deferral \| Substandard non-accrual
Financing Receivable, Modified [Line Items]
% of total class of financing receivable	7.10%		7.80%	0.90%
Term Extension, Interest Rate Reduction And Payment Deferral \| Special Mention
Financing Receivable, Modified [Line Items]
% of total class of financing receivable			8.40%
Term Extension, Interest Rate Reduction And Payment Deferral \| Commercial loans \| C&I and other commercial
Financing Receivable, Modified [Line Items]
% of total class of financing receivable	0.30%		1.00%
Term Extension, Interest Rate Reduction And Payment Deferral \| Commercial loans \| CRE and Retail real estate
Financing Receivable, Modified [Line Items]
% of total class of financing receivable	0.30%		0.30%
Term Extension
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 22,847	$ 23,210	$ 47,603	$ 34,020
Term Extension \| Commercial loans \| C&I and other commercial
Financing Receivable, Modified [Line Items]
Amortized cost basis	10,686	21,913	35,442	26,985
Term Extension \| Commercial loans \| CRE and Retail real estate
Financing Receivable, Modified [Line Items]
Amortized cost basis	12,161	1,297	12,161	1,848
Term Extension \| Commercial loans \| Real estate construction
Financing Receivable, Modified [Line Items]
Amortized cost basis				5,187
Combination—Interest Rate Reduction and Payment Deferral
Financing Receivable, Modified [Line Items]
Amortized cost basis	4,122		4,122
Combination—Interest Rate Reduction and Payment Deferral \| Commercial loans \| C&I and other commercial
Financing Receivable, Modified [Line Items]
Amortized cost basis	574		574
Combination—Interest Rate Reduction and Payment Deferral \| Commercial loans \| CRE and Retail real estate
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 3,548		3,548
Payment Deferral
Financing Receivable, Modified [Line Items]
Amortized cost basis		490	1,822	11,639
Payment Deferral \| Commercial loans \| C&I and other commercial
Financing Receivable, Modified [Line Items]
Amortized cost basis		490	1,822	11,639
Payment Deferral \| Commercial loans \| CRE and Retail real estate
Financing Receivable, Modified [Line Items]
Amortized cost basis		0	$ 0	0
Payment Deferral \| Commercial loans \| Real estate construction
Financing Receivable, Modified [Line Items]
Amortized cost basis				0
Combination—Payment Deferral and Term Extension
Financing Receivable, Modified [Line Items]
Amortized cost basis		$ 4,412		$ 4,412
% of total class of financing receivable		0.20%		0.40%
Combination—Payment Deferral and Term Extension \| Commercial loans \| C&I and other commercial
Financing Receivable, Modified [Line Items]
Amortized cost basis		$ 4,412		$ 4,412
% of total class of financing receivable		0.60%		1.00%
Combination—Payment Deferral and Term Extension \| Commercial loans \| CRE and Retail real estate
Financing Receivable, Modified [Line Items]
Amortized cost basis		$ 0		$ 0
% of total class of financing receivable		0.00%		0.00%
Combination—Payment Deferral and Term Extension \| Commercial loans \| Real estate construction
Financing Receivable, Modified [Line Items]
Amortized cost basis				$ 0
% of total class of financing receivable				0.50%