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Benefit Plans (Components of shares eligible to be issued under the Directors Plan) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |
Eligible shares, unissued | 59,162 | 27,069
Director [Member] |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |
Eligible shares, unissued | 117,053 | 177,935
Eligible shares, shares held in Rabbi Trust | 59,162 | 27,069
Eligible shares, total | 176,215 | 205,004
Market value, unissued | $ 2,291 | $ 4,326
Market value, shares held in Rabbi Trust | 1,158 | 658
Market value, total | $ 3,449 | $ 4,984

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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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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