Amount of increase (decrease) in allowance for loan and lease losses write-offs, net.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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ALLOWANCE FOR CREDIT LOSSES FOR LOANS AND FINANCE LEASES - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses	$ 245,060	$ 247,269	$ 249,037	$ 243,942
Increase (decrease) in ACL	(3,900)
Net charge-offs	21,100	21,400
Increase (decrease) in net charge-offs	(300)
Off-balance sheet credit exposures	3,120	3,080	3,013	3,143
Recoveries	6,054	6,700
Bulk Sale Of Nonaccrual Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries	2,400
Consumer Loans and Finance Leases [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Increase (decrease) in net charge-offs	1,100
Commercial And Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Increase (decrease) in net charge-offs	900
Commercial Portfolio Segment [Member] \| Virgin Islands [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Net charge-offs	600
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses	3,324	3,417	5,672	3,824
Increase (decrease) in ACL	(1,800)
Recoveries	13	14
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses	42,124	36,464	41,416	33,034
Recoveries	81	154
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses	41,534	41,640	41,071	40,654
Increase (decrease) in ACL	500
Recoveries	354	217
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for credit losses	134,408	141,605	$ 137,046	$ 143,983
Increase (decrease) in ACL	(2,600)
Recoveries	$ 5,566	$ 6,275