Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Time certificates of deposit least amount	$ 100,000	$ 100,000
Held to Maturity, Fair Value, Total	$ 534,622,000	$ 494,194,000
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, unvested restricted Stock awards	159,809	177,191
Shares Held in Rabbi Trust	157,872	164,438
Common Stock Outstanding
Common Stock, Shares, Outstanding	27,540,843	27,450,190
Junior Subordinated Debt [Member]
Unamortized Debt Issuance Expense	$ 119,000	$ 125,000
Subordinated Debt [Member]
Unamortized Debt Issuance Expense	$ 283,000	$ 318,000

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Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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