CREDIT QUALITY ASSESSMENT - Recorded Investment with Respect to Impaired loans, Associated Allowance by Applicable Portfolio Segment (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	$ 15,333
Allowance	5,501
Impaired loans without a specific allowance:	9,440
Total impaired loans:	24,773
Unpaid principal balance in total impaired loans	34,620
Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	12,652
Impaired loans without a specific allowance:	4,188
Total impaired loans:	16,840
Restructured | Accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	266
Impaired loans without a specific allowance:	2,370
Total impaired loans:	2,636
Restructured | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	2,415
Impaired loans without a specific allowance:	2,882
Total impaired loans:	5,297
All Other Loans
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Allowance	0
Impaired loans without a specific allowance:	1,717
Total impaired loans:	1,717
Unpaid principal balance in total impaired loans	2,618
All Other Loans | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Impaired loans without a specific allowance:	0
Total impaired loans:	0
All Other Loans | Restructured | Accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Impaired loans without a specific allowance:	1,444
Total impaired loans:	1,444
All Other Loans | Restructured | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Impaired loans without a specific allowance:	273
Total impaired loans:	273
Commercial real estate: | Commercial investor real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	5,885
Allowance	1,529
Impaired loans without a specific allowance:	3,327
Total impaired loans:	9,212
Unpaid principal balance in total impaired loans	13,805
Commercial real estate: | Commercial investor real estate | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	5,448
Impaired loans without a specific allowance:	2,552
Total impaired loans:	8,000
Commercial real estate: | Commercial investor real estate | Restructured | Accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Impaired loans without a specific allowance:	775
Total impaired loans:	775
Commercial real estate: | Commercial investor real estate | Restructured | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	437
Impaired loans without a specific allowance:	0
Total impaired loans:	437
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	889
Allowance	23
Impaired loans without a specific allowance:	3,259
Total impaired loans:	4,148
Unpaid principal balance in total impaired loans	6,072
Commercial real estate: | Commercial owner-occupied real estate | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	767
Impaired loans without a specific allowance:	1,522
Total impaired loans:	2,289
Commercial real estate: | Commercial owner-occupied real estate | Restructured | Accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Impaired loans without a specific allowance:	0
Total impaired loans:	0
Commercial real estate: | Commercial owner-occupied real estate | Restructured | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	122
Impaired loans without a specific allowance:	1,737
Total impaired loans:	1,859
Commercial real estate: | Commercial AD&C
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	829
Allowance	132
Impaired loans without a specific allowance:	0
Total impaired loans:	829
Unpaid principal balance in total impaired loans	829
Commercial real estate: | Commercial AD&C | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	829
Impaired loans without a specific allowance:	0
Total impaired loans:	829
Commercial real estate: | Commercial AD&C | Restructured | Accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Impaired loans without a specific allowance:	0
Total impaired loans:	0
Commercial real estate: | Commercial AD&C | Restructured | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	0
Impaired loans without a specific allowance:	0
Total impaired loans:	0
Commercial Business
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	7,730
Allowance	3,817
Impaired loans without a specific allowance:	1,137
Total impaired loans:	8,867
Unpaid principal balance in total impaired loans	11,296
Commercial Business | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	5,608
Impaired loans without a specific allowance:	114
Total impaired loans:	5,722
Commercial Business | Restructured | Accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	266
Impaired loans without a specific allowance:	151
Total impaired loans:	417
Commercial Business | Restructured | Non-accruing
Financing Receivable, Impaired [Line Items]
Impaired loans with a specific allowance:	1,856
Impaired loans without a specific allowance:	872
Total impaired loans:	$ 2,728