DEBT SECURITIES - ACL for Debt Securities Available-for-Sale (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Beginning Balance	$ 458
Ending Balance	449
Residential MBS [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Beginning Balance	83
Ending Balance	83
Puerto Rico government obligations [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Beginning Balance	400
Ending Balance	400
Available-for-sale Securities [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Beginning Balance	458	$ 1,105
Provision for credit losses - (benefit) expense	(9)	(388)
Net charge-offs		(6)
Ending Balance	449	711
Available-for-sale Securities [Member] | Residential MBS [Member] | Private label [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Beginning Balance	83	797
Provision for credit losses - (benefit) expense	0	(388)
Net charge-offs		(6)
Ending Balance	83	403
Available-for-sale Securities [Member] | Puerto Rico government obligations [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Beginning Balance	375	308
Provision for credit losses - (benefit) expense	(9)	0
Net charge-offs		0
Ending Balance	$ 366	$ 308