NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Nature of Business (Detail)	Dec. 31, 2023 subsidiaries offices numberofbranches
FirstBank [Member] | Puerto Rico [Member]
Nature Of Business [Line Items]
Number of subsidiaries | subsidiaries	6
Number of branches	58
FirstBank [Member] | U S [Member]
Nature Of Business [Line Items]
Number of branches	8
FirstBank [Member] | USVI and BVI [Member]
Nature Of Business [Line Items]
Number of branches	8
First Federal Finance Corp [Member] | Puerto Rico [Member]
Nature Of Business [Line Items]
Number of offices | offices	25