CREDIT QUALITY ASSESSMENT (Non-accrual Loans) (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2020 USD ($)
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	$ 62,612
Contractual interest income due on non- accrual loans during the period	3,420
Commercial real estate: | Commercial investor real estate
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	22,254
Contractual interest income due on non- accrual loans during the period	1,496
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	5,366
Contractual interest income due on non- accrual loans during the period	368
Commercial real estate: | Commercial AD&C
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	1,573
Contractual interest income due on non- accrual loans during the period	67
Commercial Business
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	14,932
Contractual interest income due on non- accrual loans during the period	750
Residential real estate: | Residential mortgage
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	11,990
Contractual interest income due on non- accrual loans during the period	447
Residential real estate: | Residential construction
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	0
Contractual interest income due on non- accrual loans during the period	0
Consumer
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	6,497
Contractual interest income due on non- accrual loans during the period	$ 292