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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	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 12,870,002		$ 12,746,556
ACL for loans and finance leases	(248,578)	$ (247,269)	(243,942)	$ (254,532)	$ (263,592)	$ (261,843)
Loans held for investment, net	12,621,424		12,502,614
Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	10,430,752		10,451,606
Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,439,250		2,294,950
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,859,158		2,828,431
ACL for loans and finance leases	(42,448)	(41,640)	(40,654)	(46,051)	(56,689)	(57,397)
Residential Portfolio Segment [Member] \| Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,343,894		2,323,205
Residential Portfolio Segment [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	515,264		505,226
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	245,350		228,396
ACL for loans and finance leases	(4,551)	(3,417)	(3,824)	(5,646)	(6,186)	(5,605)
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	204,485		184,427
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	40,865		43,969
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,502,475		2,565,984
ACL for loans and finance leases	(22,746)	(24,143)	(22,447)	(30,078)	(32,661)	(32,631)
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	1,774,231		1,867,894
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	728,244		698,090
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member}
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,516,008		3,366,038
ACL for loans and finance leases	(39,359)	(36,464)	(33,034)	(35,440)	(35,423)	(33,996)
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	2,367,000		2,325,875
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member} \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,149,008		1,040,163
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,747,011		3,757,707
ACL for loans and finance leases	(139,474)	$ (141,605)	(143,983)	$ (137,317)	$ (132,633)	$ (132,214)
Consumer Portfolio Segment [Member] \| Puerto Rico and Virgin Islands regions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,741,142		3,750,205
Consumer Portfolio Segment [Member] \| Florida region [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 5,869		$ 7,502