LOANS HELD FOR INVESTMENT - Loan Modifications Considered Troubled Debt Restructurings Defaulted (Detail) - TDR [Member] $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) numberofcontracts	Sep. 30, 2019 USD ($) numberofcontracts	Sep. 30, 2020 USD ($) numberofcontracts	Sep. 30, 2019 USD ($) numberofcontracts
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	50	73	142	159
Recorded Investment | $	$ 755	$ 2,634	$ 3,253	$ 3,690
Residential Portfolio Segment [Member] | Conventional Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	2	5	8	8
Recorded Investment | $	$ 253	$ 1,706	$ 2,142	$ 1,890
Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	1	0
Recorded Investment | $	$ 0	$ 0	$ 35	$ 0
Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
Commercial Portfolio Segment [Member] | Construction Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
Consumer Portfolio Segment [Member] | Auto loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	19	50	40	99
Recorded Investment | $	$ 358	$ 856	$ 681	$ 1,624
Consumer Portfolio Segment [Member] | Finance Leases [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	1	0
Recorded Investment | $	$ 0	$ 0	$ 5	$ 0
Consumer Portfolio Segment [Member] | Personal Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	1	1
Recorded Investment | $	$ 0	$ 0	$ 7	$ 9
Consumer Portfolio Segment [Member] | Credit cards [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	15	0	41	0
Recorded Investment | $	$ 80	$ 0	$ 192	$ 0
Consumer Portfolio Segment [Member] | Other Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	14	18	50	51
Recorded Investment | $	$ 64	$ 72	$ 191	$ 167
PR And VI [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	50	73	142	159
Recorded Investment | $	$ 755	$ 2,634	$ 3,253	$ 3,690
PR And VI [Member] | Residential Portfolio Segment [Member] | Conventional Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	2	5	8	8
Recorded Investment | $	$ 253	$ 1,706	$ 2,142	$ 1,890
PR And VI [Member] | Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	1	0
Recorded Investment | $	$ 0	$ 0	$ 35	$ 0
PR And VI [Member] | Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
PR And VI [Member] | Commercial Portfolio Segment [Member] | Construction Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
PR And VI [Member] | Consumer Portfolio Segment [Member] | Auto loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	19	50	40	99
Recorded Investment | $	$ 358	$ 856	$ 681	$ 1,624
PR And VI [Member] | Consumer Portfolio Segment [Member] | Finance Leases [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	1	0
Recorded Investment | $	$ 0	$ 0	$ 5	$ 0
PR And VI [Member] | Consumer Portfolio Segment [Member] | Personal Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	1	1
Recorded Investment | $	$ 0	$ 0	$ 7	$ 9
PR And VI [Member] | Consumer Portfolio Segment [Member] | Credit cards [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	15	0	41	0
Recorded Investment | $	$ 80	$ 0	$ 192	$ 0
PR And VI [Member] | Consumer Portfolio Segment [Member] | Other Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	14	18	50	51
Recorded Investment | $	$ 64	$ 72	$ 191	$ 167
FL
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Residential Portfolio Segment [Member] | Conventional Loan [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 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	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Commercial Portfolio Segment [Member] | Construction Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Consumer Portfolio Segment [Member] | Auto loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Consumer Portfolio Segment [Member] | Finance Leases [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Consumer Portfolio Segment [Member] | Personal Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Consumer Portfolio Segment [Member] | Credit cards [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
FL | Consumer Portfolio Segment [Member] | Other Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | numberofcontracts	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0