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Benefit Plans (Components of shares eligible to be issued under the Directors Plan) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |
Eligible shares, unissued | 27,069 | 16,673
Director [Member] |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |
Eligible shares, unissued | 177,935 | 203,498
Eligible shares, shares held in Rabbi Trust | 27,069 | 16,673
Eligible shares, total | 205,004 | 220,171
Market value, unissued | $ 4,326 | $ 4,591
Market value, shares held in Rabbi Trust | 658 | 376
Market value, total | $ 4,984 | $ 4,967

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- Definition Common Stock Held in Trust, Shares + References No definition available. + Details
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- Definition Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Shares + References No definition available. + Details
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- Definition Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Value + References No definition available. + Details
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- Definition Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance, Value + References No definition available. + Details
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- Details
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