Share-Based Compensation Plans (Narrative) (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 1,100,000
Aggregate intrinsic value	13,000	25,000
Total cash received as a result of option exercises	$ 72,000	$ 110,000
EPS Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
EPS percentage of award, one year performance period	30.00%
TSR Performance Requirement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR percentage of award, three year performance period	70.00%
Expected term	2 years 10 months 6 days
Risk free interest rate	0.92%
Expected dividend yield	3.53%
Expected stock price volatility	26.80%
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded	49,084
Grant date fair value	$ 16.43
Management Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded	36,384
Management Stock Incentive Plan [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock awarded	12,700
Grant date fair value	$ 22.79
Award vesting period	3 years
Required service period	3 years
Minimum [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years 6 months

Share based compensation arrangement by share based payment award, award vesting percentage, current fiscal year end

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Award Vesting Percentage, Three Year Performance Period

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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