Represents the total number of common stock shares which can be grants under the plan.

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- Definition

Share-based Compensation Arrangement by Share-base Payment Award, Percentage of Annual Retainer Received in Common Stock or Deferred Stock Rights

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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.

+ References

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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- Definition

Value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of stock value of such awards forfeited. Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Benefit Plans (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Allocated share-based compensation expense	$ 478	$ 579
Compensation cost not yet recognized	$ 3,400
Period for recognition	2 years 3 months
Percentage of annual retainer received in either common stock or deferred stock rights	100.00%
Restricted Stock Awards
Nonvested, weighted average grant date fair value	$ 24.62		$ 24.44
Plan 2013
Number of shares authorized (in shares)			750,000
Deferred Stock Units
Nonvested, weighted average grant date fair value	$ 0.00		$ 0.00
Director
Common stock shares reserved for future grants (in shares)	180,000
Director \| Restricted Stock Awards
Nonvested, weighted average grant date fair value			20
Director \| Deferred Stock Units
Nonvested, weighted average grant date fair value			$ 20
Voting and Nonvoting Common Stock \| Voting and Nonvoting Common Stock
Allocated share-based compensation expense	$ 478	$ 579