Derivatives - Summary Information Regarding Derivatives (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Third Party interest rate swaps | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Classified in Other Assets:
Notional Amount	$ 1,149,054	$ 918,758
Average Maturity (Years)	6 years 6 months	7 years 6 months
Weighted Average Fixed Rate	4.10%	3.70%
Weighted Average Variable Rate	202.00%	200.00%
Fair Value	$ 122,106	$ 94,800
Classified in Other Liabilities:
Notional Amount	$ 16,250	$ 51,864
Average Maturity (Years)	7 years	8 years 6 months
Weighted Average Fixed Rate	6.33%	5.60%
Weighted Average Variable Rate	210.00%	195.00%
Fair  Value	$ (180)	$ (1,207)
Third Party interest rate swaps | London Interbank Offered Rate (LIBOR)
Classified in Other Assets:
Notional Amount		$ 48,497
Average Maturity (Years)		1 year 6 months
Weighted Average Fixed Rate		3.40%
Weighted Average Variable Rate		252.00%
Fair Value		$ 1,841
Customer interest rate swaps | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Classified in Other Assets:
Notional Amount	$ 16,250	$ 51,864
Average Maturity (Years)	7 years	8 years 6 months
Weighted Average Fixed Rate	6.33%	5.60%
Weighted Average Variable Rate	210.00%	195.00%
Fair Value	$ 180	$ 1,207
Classified in Other Liabilities:
Notional Amount	$ 1,149,054	$ 918,758
Average Maturity (Years)	6 years 6 months	7 years 6 months
Weighted Average Fixed Rate	4.10%	3.70%
Weighted Average Variable Rate	202.00%	200.00%
Fair  Value	$ (122,110)	$ (94,800)
Customer interest rate swaps | London Interbank Offered Rate (LIBOR)
Classified in Other Liabilities:
Notional Amount		$ 48,497
Average Maturity (Years)		1 year 6 months
Weighted Average Fixed Rate		3.40%
Weighted Average Variable Rate		252.00%
Fair  Value		$ (1,841)