CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION
Debt securities held to maturity, fair value	$ 198,147	$ 189,221	$ 202,266	$ 209,376	$ 209,887
Preferred stock, no par value	$ 0	$ 0	$ 0	$ 0	$ 0
Preferred stock, shares authorized	500,000	500,000	500,000	500,000	500,000
Preferred stock, shares issued	0	0	0	0	0
Common stock, par or stated value per share	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Common stock, shares authorized	20,000,000	20,000,000	20,000,000	20,000,000	20,000,000
Common stock, shares issued	5,151,279	5,151,279	5,151,279	5,151,279	5,151,279
Common stock, shares outstanding	4,991,129	5,018,129	5,018,129	5,013,899	5,003,059
Treasury stock, shares outstanding	160,150	133,150	133,150	137,380	148,220