CREDIT QUALITY ASSESSMENT - Collateral dependent loans individually evaluated for credit loss (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	$ 53,007	$ 20,717
Allowance related to loans evaluated individually	16,283	11,405
Loans individually evaluated for credit loss without an allowance	23,910	77,001
Total individually evaluated collateral dependent loans	76,917	97,718
Total unpaid contractual principal balance	87,879	115,816
Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	50,053	17,419
Loans individually evaluated for credit loss without an allowance	9,157	71,764
Total individually evaluated collateral dependent loans	59,210	89,183
Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	2,408	2,709
Loans individually evaluated for credit loss without an allowance	13,071	3,509
Total individually evaluated collateral dependent loans	15,479	6,218
Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	546	589
Loans individually evaluated for credit loss without an allowance	1,682	1,728
Total individually evaluated collateral dependent loans	2,228	2,317
Commercial real estate: | Commercial investor real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	28,382	5,612
Allowance related to loans evaluated individually	6,893	1,273
Loans individually evaluated for credit loss without an allowance	13,690	39,615
Total individually evaluated collateral dependent loans	42,072	45,227
Total unpaid contractual principal balance	47,061	49,920
Commercial real estate: | Commercial investor real estate | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	28,046	4,913
Loans individually evaluated for credit loss without an allowance	5,677	39,615
Total individually evaluated collateral dependent loans	33,723	44,528
Commercial real estate: | Commercial investor real estate | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	336	699
Loans individually evaluated for credit loss without an allowance	8,013	0
Total individually evaluated collateral dependent loans	8,349	699
Commercial real estate: | Commercial investor real estate | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	883	0
Allowance related to loans evaluated individually	143	0
Loans individually evaluated for credit loss without an allowance	7,300	11,561
Total individually evaluated collateral dependent loans	8,183	11,561
Total unpaid contractual principal balance	10,214	15,309
Commercial real estate: | Commercial owner-occupied real estate | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	883	0
Loans individually evaluated for credit loss without an allowance	3,177	9,315
Total individually evaluated collateral dependent loans	4,060	9,315
Commercial real estate: | Commercial owner-occupied real estate | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	4,123	2,246
Total individually evaluated collateral dependent loans	4,123	2,246
Commercial real estate: | Commercial owner-occupied real estate | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial real estate: | Commercial AD&C
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	14,489	1,328
Allowance related to loans evaluated individually	2,352	603
Loans individually evaluated for credit loss without an allowance	0	13,716
Total individually evaluated collateral dependent loans	14,489	15,044
Total unpaid contractual principal balance	15,696	16,040
Commercial real estate: | Commercial AD&C | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	14,489	1,328
Loans individually evaluated for credit loss without an allowance	0	13,716
Total individually evaluated collateral dependent loans	14,489	15,044
Commercial real estate: | Commercial AD&C | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial real estate: | Commercial AD&C | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial Business
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	9,253	13,777
Allowance related to loans evaluated individually	6,895	9,529
Loans individually evaluated for credit loss without an allowance	836	9,871
Total individually evaluated collateral dependent loans	10,089	23,648
Total unpaid contractual principal balance	11,744	30,958
Commercial Business | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	6,635	11,178
Loans individually evaluated for credit loss without an allowance	303	9,118
Total individually evaluated collateral dependent loans	6,938	20,296
Commercial Business | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	2,072	2,010
Loans individually evaluated for credit loss without an allowance	425	627
Total individually evaluated collateral dependent loans	2,497	2,637
Commercial Business | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	546	589
Loans individually evaluated for credit loss without an allowance	108	126
Total individually evaluated collateral dependent loans	654	715
Residential real estate: | Residential mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Allowance related to loans evaluated individually	0	0
Loans individually evaluated for credit loss without an allowance	1,724	1,874
Total individually evaluated collateral dependent loans	1,724	1,874
Total unpaid contractual principal balance	2,800	3,225
Residential real estate: | Residential mortgage | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Residential real estate: | Residential mortgage | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	150	272
Total individually evaluated collateral dependent loans	150	272
Residential real estate: | Residential mortgage | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	1,574	1,602
Total individually evaluated collateral dependent loans	1,574	1,602
Residential real estate: | Residential construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Allowance related to loans evaluated individually	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Total unpaid contractual principal balance	0	0
Residential real estate: | Residential construction | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Residential real estate: | Residential construction | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Residential real estate: | Residential construction | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Allowance related to loans evaluated individually	0	0
Loans individually evaluated for credit loss without an allowance	360	364
Total individually evaluated collateral dependent loans	360	364
Total unpaid contractual principal balance	364	364
Consumer | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Consumer | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	360	364
Total individually evaluated collateral dependent loans	360	364
Consumer | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	$ 0	$ 0