LOANS HELD FOR INVESTMENT - Collateral dependent loans individually evaluated for purposes of determining the ACL (Detail) - Collateral Pledged [Member] $ in Thousands	Sep. 30, 2020 USD ($)
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	$ 165,757
Related Specific Allowance	21,240
Amortized Cost no ACL	73,499
Amortized Cost	239,256
Residential Portfolio Segment [Member] | Loans Insured or Guaranteed by US Government Authorities [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
Residential Portfolio Segment [Member] | Conventional Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	109,215
Related Specific Allowance	11,262
Amortized Cost no ACL	9,750
Amortized Cost	118,965
Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	31,151
Related Specific Allowance	6,791
Amortized Cost no ACL	16,847
Amortized Cost	47,998
Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	17,978
Related Specific Allowance	2,572
Amortized Cost no ACL	44,216
Amortized Cost	62,194
Commercial Portfolio Segment [Member] | Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	6,036
Related Specific Allowance	491
Amortized Cost no ACL	2,686
Amortized Cost	8,722
Consumer Portfolio Segment [Member] | Automobile Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
Consumer Portfolio Segment [Member] | Finance Leases [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
Consumer Portfolio Segment [Member] | Personal Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	146
Related Specific Allowance	5
Amortized Cost no ACL	0
Amortized Cost	146
Consumer Portfolio Segment [Member] | Credit Card Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
Consumer Portfolio Segment [Member] | Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	1,231
Related Specific Allowance	119
Amortized Cost no ACL	0
Amortized Cost	1,231
PR And VI [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	155,387
Related Specific Allowance	19,563
Amortized Cost no ACL	68,041
Amortized Cost	223,428
PR And VI [Member] | Residential Portfolio Segment [Member] | Loans Insured or Guaranteed by US Government Authorities [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
PR And VI [Member] | Residential Portfolio Segment [Member] | Conventional Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	99,839
Related Specific Allowance	9,935
Amortized Cost no ACL	9,750
Amortized Cost	109,589
PR And VI [Member] | Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	30,405
Related Specific Allowance	6,475
Amortized Cost no ACL	16,600
Amortized Cost	47,005
PR And VI [Member] | Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	17,978
Related Specific Allowance	2,572
Amortized Cost no ACL	39,005
Amortized Cost	56,983
PR And VI [Member] | Commercial Portfolio Segment [Member] | Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	6,036
Related Specific Allowance	491
Amortized Cost no ACL	2,686
Amortized Cost	8,722
PR And VI [Member] | Consumer Portfolio Segment [Member] | Automobile Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
PR And VI [Member] | Consumer Portfolio Segment [Member] | Finance Leases [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
PR And VI [Member] | Consumer Portfolio Segment [Member] | Personal Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	146
Related Specific Allowance	5
Amortized Cost no ACL	0
Amortized Cost	146
PR And VI [Member] | Consumer Portfolio Segment [Member] | Credit Card Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
PR And VI [Member] | Consumer Portfolio Segment [Member] | Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	983
Related Specific Allowance	85
Amortized Cost no ACL	0
Amortized Cost	983
FL
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	10,370
Related Specific Allowance	1,677
Amortized Cost no ACL	5,458
Amortized Cost	15,828
FL | Residential Portfolio Segment [Member] | Loans Insured or Guaranteed by US Government Authorities [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
FL | Residential Portfolio Segment [Member] | Conventional Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	9,376
Related Specific Allowance	1,327
Amortized Cost no ACL	0
Amortized Cost	9,376
FL | Commercial Portfolio Segment [Member] | Commercial And Industrial Sector [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	746
Related Specific Allowance	316
Amortized Cost no ACL	247
Amortized Cost	993
FL | Commercial Portfolio Segment [Member] | Mortgage Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	5,211
Amortized Cost	5,211
FL | Commercial Portfolio Segment [Member] | Construction Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
FL | Consumer Portfolio Segment [Member] | Automobile Loan [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
FL | Consumer Portfolio Segment [Member] | Finance Leases [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
FL | Consumer Portfolio Segment [Member] | Personal Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
FL | Consumer Portfolio Segment [Member] | Credit Card Receivable [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	0
Related Specific Allowance	0
Amortized Cost no ACL	0
Amortized Cost	0
FL | Consumer Portfolio Segment [Member] | Other Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Amortized Cost with ACL	248
Related Specific Allowance	34
Amortized Cost no ACL	0
Amortized Cost	$ 248