CREDIT QUALITY ASSESSMENT - Non-accrual Loans (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	$ 99,920	$ 72,562
Contractual interest income due on non- accrual loans during the period	2,942	18,301
Commercial real estate: | Commercial investor real estate
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	43,358	26,849
Contractual interest income due on non- accrual loans during the period	1,221	6,547
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	9,353	6,605
Contractual interest income due on non- accrual loans during the period	361	2,741
Commercial real estate: | Commercial AD&C
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	14,836	4,267
Contractual interest income due on non- accrual loans during the period	519	4,505
Commercial Business
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	15,172	16,532
Contractual interest income due on non- accrual loans during the period	409	2,858
Residential real estate: | Residential mortgage
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	9,748	11,634
Contractual interest income due on non- accrual loans during the period	218	918
Residential real estate: | Residential construction
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	21	0
Contractual interest income due on non- accrual loans during the period	1	0
Consumer
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	7,432	6,675
Contractual interest income due on non- accrual loans during the period	$ 213	$ 732