CONSOLIDATED STATEMENTS OF CONDITION (UNAUDITED) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Statement of Financial Position [Abstract]
Securities held to maturity, fair value	$ 9,451	$ 10,768	$ 18,565
Allowance for loan losses	$ 20,237	$ 20,226	$ 15,852
Preferred stock, par value (in dollars per share)	$ 2.50	$ 2.50	$ 2.50
Preferred stock, shares authorized	20,000,000	20,000,000	20,000,000
Preferred stock, shares outstanding	0	0	0
Common stock, par value (in dollars per share)	$ 2.50	$ 2.50	$ 2.50
Common stock, shares authorized	20,000,000	20,000,000	20,000,000
Common stock, shares issued	8,777,620	8,771,993	8,732,506
Common stock, shares outstanding	8,715,020	8,709,393	8,669,906
Treasury stock, shares	62,600	62,600	62,600