CREDIT QUALITY ASSESSMENT - Impaired Loans by Portfolio (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Financing Receivable, Impaired [Line Items]
Average impaired loans for the period	$ 23,365
Contractual interest income due on impaired loans during the period	1,947
Interest income on impaired loans recognized on an accrual basis	169
All Other Loans
Financing Receivable, Impaired [Line Items]
Average impaired loans for the period	1,577
Contractual interest income due on impaired loans during the period	128
Interest income on impaired loans recognized on an accrual basis	68
Commercial real estate: | Commercial investor real estate
Financing Receivable, Impaired [Line Items]
Average impaired loans for the period	7,565
Contractual interest income due on impaired loans during the period	786
Interest income on impaired loans recognized on an accrual basis	39
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Impaired [Line Items]
Average impaired loans for the period	4,390
Contractual interest income due on impaired loans during the period	258
Interest income on impaired loans recognized on an accrual basis	0
Commercial real estate: | Commercial AD&C
Financing Receivable, Impaired [Line Items]
Average impaired loans for the period	2,052
Contractual interest income due on impaired loans during the period	127
Interest income on impaired loans recognized on an accrual basis	0
Commercial Business
Financing Receivable, Impaired [Line Items]
Average impaired loans for the period	7,781
Contractual interest income due on impaired loans during the period	648
Interest income on impaired loans recognized on an accrual basis	$ 62