Earnings Per Common Share And Share Awards (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Common Share And Share Awards [Line Items]
Incremental dilutive potential common shares, calculated using treasury stock method (in shares)	5,412	4,797	6,559	5,160
Anti-dilutive shares excluded from computation of diluted earnings per share	0	4,500	4,500	4,500
SARs and options vesting period			1 year
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			4,500	4,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 28.75	$ 31.16
Compensation expense relating to SARs or options vesting			$ 67,000	$ 68,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 97,000		$ 97,000
Number of stock options or SARs granted where exercise price was less than market price on date of grant			0	0
Minimum
Earnings Per Common Share And Share Awards [Line Items]
SARs and options expiration period			5 years
Maximum
Earnings Per Common Share And Share Awards [Line Items]
Maximum shares of Company stock to be granted to key employees or directors			250,000
SARs and options expiration period			7 years

Earnings Per Common Share And Share Awards [Line Items]

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- Definition

Number of stock options or SARs granted where exercise price was less than market price on date of grant.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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