LOANS HELD FOR INVESTMENT - Loan Portfolio Held for Investment (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loans held for investment	$ 12,185,483	$ 11,552,825
ACL for loans and finance leases	(261,843)	(260,464)	$ (269,030)	$ (385,887)
Loans held for investment, net	11,923,640	11,292,361
Puerto Rico and Virgin Islands regions [Member]
Loans held for investment	10,163,222	9,464,474
Florida region [Member}
Loans held for investment	2,022,261	2,088,351	1,948,716
Residential Portfolio Segment [Member]
Loans held for investment	2,821,726	2,847,290
ACL for loans and finance leases	(57,397)	(62,760)	(74,837)	(120,311)
Residential Portfolio Segment [Member] \| Puerto Rico and Virgin Islands regions [Member]
Loans held for investment	2,356,006	2,417,900
Residential Portfolio Segment [Member] \| Florida region [Member}
Loans held for investment	465,720	429,390
Commercial Portfolio Segment [Member] \| C & I Loans [Member]
Loans held for investment	3,174,232	2,886,263
ACL for loans and finance leases	(33,190)	(32,906)	(34,284)	(37,944)
Commercial Portfolio Segment [Member] \| C & I Loans [Member] \| Puerto Rico and Virgin Islands regions [Member]
Loans held for investment	2,249,408	1,860,109
Commercial Portfolio Segment [Member] \| C & I Loans [Member] \| Florida region [Member}
Loans held for investment	924,824	1,026,154
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Loans held for investment	2,317,083	2,358,851
ACL for loans and finance leases	(32,631)	(35,064)	(52,771)	(109,342)
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member] \| Puerto Rico and Virgin Islands regions [Member]
Loans held for investment	1,790,637	1,834,204
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member] \| Florida region [Member}
Loans held for investment	526,446	524,647
Commercial Portfolio Segment [Member] \| Construction loans [Member]
Loans held for investment	214,777	132,953
ACL for loans and finance leases	(5,605)	(2,308)	(4,048)	(5,380)
Commercial Portfolio Segment [Member] \| Construction loans [Member] \| Puerto Rico and Virgin Islands regions [Member]
Loans held for investment	115,401	34,772
Commercial Portfolio Segment [Member] \| Construction loans [Member] \| Florida region [Member}
Loans held for investment	99,376	98,181
Consumer Portfolio Segment [Member]
Loans held for investment	3,657,665	3,327,468
ACL for loans and finance leases	(133,020)	(127,426)	$ (103,090)	$ (112,910)
Consumer Portfolio Segment [Member] \| Puerto Rico and Virgin Islands regions [Member]
Loans held for investment	3,651,770	3,317,489
Consumer Portfolio Segment [Member] \| Florida region [Member}
Loans held for investment	$ 5,895	$ 9,979

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

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+ References

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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
-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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