Derivatives - Summary Information Regarding Derivatives (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
3rd Party interest rate swaps
Classified in Other Assets:
Notional Amount	$ 265,427	$ 73,075
Average Maturity (Years)	8 years 8 months 12 days	9 years 6 months
Weighted Average Fixed Rate	3.08%	3.20%
Weighted Average Variable Rate	228.00%	255.00%
Fair Value	$ 6,968	$ 503
Classified in Other Liabilities:
Notional Amount	$ 721,962	$ 907,069
Average Maturity (Years)	8 years 3 months 18 days	8 years 8 months 12 days
Weighted Average Fixed Rate	3.90%	3.79%
Weighted Average Variable Rate	193.00%	199.00%
Fair  Value	$ (47,244)	$ (80,231)
Customer interest rate swaps
Classified in Other Assets:
Notional Amount	$ 721,962	$ 907,069
Average Maturity (Years)	8 years 3 months 18 days	8 years 8 months 12 days
Weighted Average Fixed Rate	3.90%	3.79%
Weighted Average Variable Rate	193.00%	199.00%
Fair Value	$ 47,244	$ 80,231
Classified in Other Liabilities:
Notional Amount	$ 265,427	$ 73,075
Average Maturity (Years)	8 years 8 months 12 days	9 years 6 months
Weighted Average Fixed Rate	3.08%	3.20%
Weighted Average Variable Rate	228.00%	255.00%
Fair  Value	$ (6,968)	$ (503)
Interest rate swap (cash flow hedge)
Classified in Other Liabilities:
Notional Amount	$ 10,000	$ 30,000
Average Maturity (Years)	1 month 6 days	6 months
Weighted Average Fixed Rate	1.10%	1.10%
Fair  Value	$ (8)	$ (143)