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Benefit Plans (Components of shares eligible to be issued under the Directors Plan) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Eligible shares, unissued	16,673	31,769
Director [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Eligible shares, unissued	203,498	195,140
Eligible shares, shares held in Rabbi Trust	16,673	31,769
Eligible shares, total	220,171	226,909
Market value, unissued	$ 4,591	$ 5,513
Market value, shares held in Rabbi Trust	376	897
Market value, total	$ 4,967	$ 6,410

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- Definition

Common Stock Held in Trust, Shares

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- Definition

Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Shares

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- Definition

Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Value

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No definition available.

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- Definition

Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance, Value

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- Definition

Value of common stock held in trust.

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- Definition

Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

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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.

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No definition available.

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