LOANS HELD FOR INVESTMENT - Loan Modifications Considered Troubled Debt Restructurings Defaulted (Detail) - TDR $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) numberofcontracts	Dec. 31, 2019 USD ($) numberofcontracts	Dec. 31, 2018 USD ($) numberofcontracts
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	175	220	134
Recorded investment | $	$ 3,900	$ 4,501	$ 3,225
Residential Portfolio Segment [Member] | Conventional Loan [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	10	11	15
Recorded investment | $	$ 2,380	$ 2,019	$ 1,994
Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	3	0	0
Recorded investment | $	$ 124	$ 0	$ 0
Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
Construction Loans [Member] | Commercial Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
Auto loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	55	130	62
Recorded investment | $	$ 947	$ 2,221	$ 1,003
Finance Leases [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	1	1	1
Recorded investment | $	$ 5	$ 14	$ 22
Personal Loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	1	1	2
Recorded investment | $	$ 7	$ 9	$ 26
Credit Cards | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	47	0	0
Recorded investment | $	$ 228	$ 0	$ 0
Other Loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	58	77	54
Recorded investment | $	$ 209	$ 238	$ 180
PR And VI [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	175	220	134
Recorded investment | $	$ 3,900	$ 4,501	$ 3,225
PR And VI [Member] | Residential Portfolio Segment [Member] | Conventional Loan [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	10	11	15
Recorded investment | $	$ 2,380	$ 2,019	$ 1,994
PR And VI [Member] | Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	3	0	0
Recorded investment | $	$ 124	$ 0	$ 0
PR And VI [Member] | Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
PR And VI [Member] | Construction Loans [Member] | Commercial Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
PR And VI [Member] | Auto loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	55	130	62
Recorded investment | $	$ 947	$ 2,221	$ 1,003
PR And VI [Member] | Finance Leases [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	1	1	1
Recorded investment | $	$ 5	$ 14	$ 22
PR And VI [Member] | Personal Loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	1	1	2
Recorded investment | $	$ 7	$ 9	$ 26
PR And VI [Member] | Credit Cards | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	47	0	0
Recorded investment | $	$ 228	$ 0	$ 0
PR And VI [Member] | Other Loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	58	77	54
Recorded investment | $	$ 209	$ 238	$ 180
FL
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Residential Portfolio Segment [Member] | Conventional Loan [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Construction Loans [Member] | Commercial Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Auto loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Finance Leases [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Personal Loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Credit Cards | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0
FL | Other Loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable Modifications [Line Items]
Number of contracts | numberofcontracts	0	0	0
Recorded investment | $	$ 0	$ 0	$ 0