The percentage of shares awarded that will vest after the stated term.

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- Definition

The estimated weighted average fair value of stock options granted during the period, using Black-Scholes option pricing model.

+ References

No definition available.

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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

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-Name Staff Accounting Bulletin (SAB)

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-Section F

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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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

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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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).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Name Accounting Standards Codification

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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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- 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.

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-Name Staff Accounting Bulletin (SAB)

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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

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

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- Definition

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

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Benefit Plans, Valuation, Stock-Based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	$ 1,200	$ 847	$ 447
Stock Options [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Options maximum term	5 years
Unrecognized stock-based compensation expense related to non-vested stock options	569
Unrecognized compensation expense, period of recognition	3 years 6 months
Weighted average fair value of stock options granted (in dollars per share)	$ 0.93	$ 1.08	$ 0.76
Shares [Roll Forward]
Shares issued (in shares)	188,250
Restricted Common Shares [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	141	170	170
Unrecognized stock-based compensation expense		151	333
Shares [Roll Forward]
Balance, December 31, 2013 (in shares)	106,000
New awards granted (in shares)	0
Awards became vested or settled (in shares)	(106,000)
Balance, December 31, 2014 (in shares)	0	106,000
Shares issued (in shares)				99,000
Shares vested after term (in hundredths)			100.00%
Awards granted, fair value			$ 5.14
Restricted Shares Units [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	352	230	23
Options maximum term	3 years
Unrecognized stock-based compensation expense	864
Unrecognized compensation expense, period of recognition	26 months
Shares [Roll Forward]
Balance, December 31, 2013 (in shares)	133,750
New awards granted (in shares)	68,650
Awards became vested or settled (in shares)	0
Balance, December 31, 2014 (in shares)	202,400	133,750
Shares vested after term (in hundredths)	100.00%
Liability related to awards	605	253
Performance Share Units [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	490	239	19
Options maximum term	3 years
Unrecognized stock-based compensation expense	1,200
Unrecognized compensation expense, period of recognition	26 months
Shares [Roll Forward]
Balance, December 31, 2013 (in shares)	146,500
New awards granted (in shares)	83,000
Awards became vested or settled (in shares)	0
Balance, December 31, 2014 (in shares)	229,500	146,500
Shares vested after term (in hundredths)	100.00%
Liability related to awards	748	258
Liability Awards [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	870	469	42
Equity Awards [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	325	378	405
Employees' Plan [Member]
Assumption used to determine fair value of options [Abstract]
Expected dividend yield (in hundredths)	3.64%	3.72%	5.08%
Risk-free interest rate (in hundredths)	1.74%	1.45%	0.80%
Expected volatility rate (in hundredths)	21.62%	25.83%	30.18%
Expected lives	5 years	5 years	5 years
Directors' Plan [Member] \| Restricted Common Shares [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	$ 10	$ 12	$ 12
Shares [Roll Forward]
Shares issued (in shares)				7,000