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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	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 13,091,077	$ 13,125,356
ACL for loans and finance leases	(245,060)	(249,037)	$ (247,269)	$ (243,942)
Loans held for investment, net	12,846,017	12,876,319
Puerto Rico and Virgin Islands region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	10,545,715	10,627,192
Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,545,362	2,498,164
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,914,898	2,908,302
ACL for loans and finance leases	(41,534)	(41,071)	(41,640)	(40,654)
Residential Portfolio Segment [Member] \| Puerto Rico and Virgin Islands region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,378,388	2,377,604
Residential Portfolio Segment [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	536,510	530,698
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	195,267	265,568
ACL for loans and finance leases	(3,324)	(5,672)	(3,417)	(3,824)
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Puerto Rico and Virgin Islands region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	192,977	263,640
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,290	1,928
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,627,113	2,554,252
ACL for loans and finance leases	(23,670)	(23,832)	(24,143)	(22,447)
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| Puerto Rico and Virgin Islands region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,826,549	1,763,927
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	800,564	790,325
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member}
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,694,843	3,688,358
ACL for loans and finance leases	(42,124)	(41,416)	(36,464)	(33,034)
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member} \| Puerto Rico and Virgin Islands region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,494,701	2,519,002
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member} \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,200,142	1,169,356
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,658,956	3,708,876
ACL for loans and finance leases	(134,408)	(137,046)	$ (141,605)	$ (143,983)
Consumer Portfolio Segment [Member] \| Puerto Rico and Virgin Islands region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,653,100	3,703,019
Consumer Portfolio Segment [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 5,856	$ 5,857