Credit Quality - Schedule of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	$ 22,389	$ 4,743	$ 32,393	$ 5,397
Interest rate reduction [Member]
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	2,675	0	10,028	251
Interest rate reduction and change in terms [Member]
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	1,326	0	1,326	0
Forgiveness of principal [Member]
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	252	0	252	0
Transfer of asset [Member]
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	121	0	121	0
Concession of principal and term [Member]
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	24	0	24	0
Extended maturity [Member]
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	4,879	0	4,879	0
Change in terms [Member]
Disclosure Details Of Troubled Debt Restructuring Loan Modification Based On Post Modification Outstanding Balance [Line Items]
Post-Modification Outstanding Recorded Investment	$ 13,112	$ 4,743	$ 15,763	$ 5,146