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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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LOANS HELD FOR INVESTMENT - Loan Portfolio Held for Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 12,746,556	$ 12,185,483
ACL for loans and finance leases	(243,942)	(261,843)	$ (260,464)	$ (269,030)
Loans held for investment, net	12,502,614	11,923,640
Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	10,451,606	10,163,222
Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,294,950	2,022,261
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,828,431	2,821,726
ACL for loans and finance leases	(40,654)	(57,397)	(62,760)	(74,837)
Residential Portfolio Segment [Member] \| Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,323,205	2,356,006
Residential Portfolio Segment [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	505,226	465,720
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	228,396	214,777
ACL for loans and finance leases	(3,824)	(5,605)	(2,308)	(4,048)
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	184,427	115,401
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	43,969	99,376
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,565,984	2,317,083
ACL for loans and finance leases	(22,447)	(32,631)	(35,064)	(52,771)
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,867,894	1,790,637
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	698,090	526,446
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member}
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,366,038	3,174,232
ACL for loans and finance leases	(32,266)	(33,190)	(32,906)	(34,284)
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member} \| Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,325,875	2,249,408
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member} \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,040,163	924,824
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,757,707	3,657,665
ACL for loans and finance leases	(144,751)	(133,020)	$ (127,426)	$ (103,090)
Consumer Portfolio Segment [Member] \| Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,750,205	3,651,770
Consumer Portfolio Segment [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 7,502	$ 5,895