Stock-based Compensation (Schedule of SARs Oustanding) (Details) - SARs [Member]	12 Months Ended
Dec. 31, 2019 $ / shares shares
SARs
Balance at December 31, 2018 \| shares	237,121
Exercised \| shares	(81,829)
Forfeited \| shares
Balance at December 31, 2019 \| shares	155,292
Exercisable at December 31, 2019 \| shares	155,292
Weighted Average Exercise Price
Balance at December 31, 2018 \| $ / shares	$ 29.86
Exercised \| $ / shares	24.71
Forfeited \| $ / shares
Balance at December 31, 2019 \| $ / shares	32.58
Exercisable at December 31, 2019 \| $ / shares	$ 32.58

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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No definition available.

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- Definition

Number of shares (or other type of equity) forfeited during the period.

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No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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