LOANS HELD FOR INVESTMENT - Additional Information V (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 12,746,556	$ 12,185,483
Loans modified to borrowers experiencing financial difficulty	146,403	39,569
United States [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,294,950	2,022,261
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	228,396	214,777
Loans modified to borrowers experiencing financial difficulty	120	0
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| United States [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	43,969	99,376
Commercial Portfolio Segment [Member] \| Government [Member] \| Puerto Rico [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	193,300	174,900
Commercial Portfolio Segment [Member] \| Government [Member] \| V I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	100,400	90,500
Commercial Portfolio Segment [Member] \| Government [Member] \| Public Corporation [Member] \| Puerto Rico [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	30,100
Commercial Portfolio Segment [Member] \| Government [Member] \| Property Tax Revenue [Member] \| Puerto Rico [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	132,200
Commercial Portfolio Segment [Member] \| Government [Member] \| Municipal Special Obligation Bond [Member] \| Puerto Rico [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	22,200
Commercial Portfolio Segment [Member] \| Government [Member] \| Puerto Rico Electric Power Authority [Member] \| Puerto Rico [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	8,800
Commercial Portfolio Segment [Member] \| Government [Member] \| Low-Income Housing Tax Credit And Community Development Block Grant-Disaster Recovery [Member] \| Construction Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	59,200	12,800
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,828,431	2,821,726
Residential Portfolio Segment [Member] \| United States [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	505,226	465,720
Residential Portfolio Segment [Member] \| Loans Insured or Guaranteed by US Government Authorities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	92,252	100,236
Loans modified to borrowers experiencing financial difficulty	4,500	3,900
Residential Portfolio Segment [Member] \| Loans Insured or Guaranteed by US Government Authorities [Member] \| United States [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,128	943
Residential Portfolio Segment [Member] \| Government [Member] \| Puerto Rico Housing Finance Authority [Member] \| Puerto Rico [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 72,500	$ 77,700
Product Concentration Risk [Member] \| Loans and Finance Receivables [Member] \| Puerto Rico [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Credit risk concentration	79.00%
Product Concentration Risk [Member] \| Loans and Finance Receivables [Member] \| United States [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Credit risk concentration	18.00%
Product Concentration Risk [Member] \| Loans and Finance Receivables [Member] \| USVI and BVI [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Credit risk concentration	3.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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