Estimated performance period which is required for the equity-based payment award.

No definition available.

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- Definition

Fair value of equity-based compensation awards granted. Excludes stock and unit options.

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No definition available.

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- Definition

Additional stock-based compensation cost that the entity expects to record for awards outstanding for the remainder of the calendar year since from the most recent balance sheet.

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No definition available.

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- Definition

Represents the number of share-based compensation plans of the entity.

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No definition available.

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- Definition

Gross number of share stock options granted since 2007.

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No definition available.

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- Definition

The period of time, from the grant date until the time at which the share-based award expires.

+ References

No definition available.

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- Definition

Annual Percentage of awards that are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the awards to shares (in case of options) or receive the full benefits of the awards.

+ 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Name Staff Accounting Bulletin (SAB)

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-Section F

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- Definition

The amount of expense, net of income tax, 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

No definition available.

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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.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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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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- 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).

+ References

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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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-Publisher FASB

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Subparagraph (SAB TOPIC 14.D.2)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Stock-Based Compensation (Details) (USD $)	0 Months Ended	3 Months Ended		12 Months Ended
Stock-Based Compensation (Details) (USD $)	Apr. 22, 2015	Mar. 31, 2015 plan	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Stock-Based Compensation
Number of stock-based compensation plans		1
Number of additional shares authorized under the plan	0
Number of shares available for future awards		350,852
Stock-based compensation
Stock-based compensation expense before income taxes		$ 501,000	$ 290,000
Less: deferred tax benefit		(176,000)	(102,000)
Reduction of net income		325,000	188,000
Additional expected stock-based compensation expense		1,600,000
Unrecognized stock-based compensation expense		5,100,000
Period of recognition of stock-based compensation expense		5 years
Amount received from exercise of options		296,000	463,000
Options and SARs
Stock-based compensation
Award vesting limit per year (as a percent)		20.00%
Period after grant date after which the award expires		10 years
Stock options granted since 2007		0
Assumptions used in SAR/Option valuations
Dividend yield (as a percent)		2.97%	2.94%
Expected volatility (as a percent)		22.81%	23.66%
Risk free interest rate (as a percent)		1.91%	2.22%
Expected life of awards		7 years 6 months	7 years
Restricted stock
Stock-based compensation
Award vesting period		5 years
Shares awarded (in shares)		34,890		39,730
Performance stock units \| Executive Officer
Stock-Based Compensation
Number of shares available for future awards		19,774		25,012	36,792
Stock-based compensation
Award vesting period		3 years		3 years	3 years
Performance period		3 years
Restricted stock units (RSUs) \| Directors
Stock-based compensation
Award vesting period		12 months
Shares awarded (in shares)		6,080
Fair value on grant date		$ 200,000