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Earnings Per Share (Narrative) (Details) | 3 Months Ended
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Mar. 31, 2020 item shares | Mar. 31, 2019 shares
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |
Number of active share-based compensation plans | item | 2 |
Potentially dilutive common shares | 34,373 | 40,766
Stock-Settled Stock Appreciation Rights (SSARs) [Member] |  |
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |
Potentially dilutive common shares | 28,070 | 29,708
Restricted Stock [Member] |  |
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |
Potentially dilutive common shares | 6,303 | 11,058

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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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- Definition The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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