Refers to the amount of monthly meeting fees that a director could receive if restricted stock vested.

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Refers to the amount of monthly meeting fees that a director could receive in cash.

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Refers to the number of directors elected to receive stock in lieu of cash out of total.

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Refers to the amount of regular quarterly retainer that a director could receive in cash.

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Refers to the amount of regular quarterly retainer if restricted stock vested.

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No definition available.

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Refers to vesting period of granted restricted stock.

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Amount of increase to additional paid-in capital (APIC) resulting from recognition of equity-based compensation for restricted stock units.

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

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

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Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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).

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

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Percentage of vesting of share-based compensation awards.

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Stock Based Compensation - Additional Information (Details)	9 Months Ended
	Sep. 30, 2017 USD ($) director shares	Sep. 30, 2016 USD ($) shares	Dec. 31, 2016 USD ($)	Apr. 22, 2008 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of common stock authorizes for issuance (in shares) \| shares				500,000
Unrecognized compensation expense	$ 0
Regular quarterly board retainer director could receive in cash	5,800
Regular quarterly board retainer if restricted stock vested	6,250
Monthly meeting fees a director could receive in cash	725
Monthly meeting fees a director could receive if restricted stock vested	$ 900
Number of directors elected to receive stock in lieu of cash \| director	12
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum vesting period of granted restricted stock	36 months
Unrecognized compensation expense	$ 651,000		$ 568,000
Weighted average period for recognition of unrecognized compensation cost	1 year 4 months
Share based compensation expense	$ 418,000	$ 342,000
Number of shares issued (in shares) \| shares	9,891	10,588
Recognized share based compensation expense	$ 357,000	$ 281,000
Restricted Stock \| Vesting 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of remainder of restricted stock vesting each year	33.00%
Restricted Stock \| Vesting 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of remainder of restricted stock vesting each year	33.00%
Restricted Stock \| Vesting 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of remainder of restricted stock vesting each year	33.00%