Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Time certificates of deposit least amount	$ 100,000	$ 100,000
Held to Maturity, Fair Value, Total	690,467,000	753,263,000
Debt Securities, Available-for-sale, Amortized Cost	$ 404,159,000	$ 420,703,000
Preferred Stock, par value	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	1,000,000	1,000,000
Preferred Stock, shares outstanding	0	0
Common Stock, par value	$ 0.01	$ 0.01
Common Stock, shares authorized	75,000,000	75,000,000
Common Stock, Shares, Outstanding	32,955,547	34,377,388
Common Stock, unvested restricted Stock awards	137,457	147,184
Shares Held in Rabbi Trust	135,111	143,820
Common Stock Outstanding
Common Stock, Shares, Outstanding	32,955,547	34,377,388
Subordinated Debt [Member]
Unamortized Debt Issuance Expense	$ 328,000	$ 399,000
Long-term Debt [Member]
Unamortized Debt Issuance Expense	$ 53,000	$ 94,000