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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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Number of Directors

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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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Amount of equity-based compensation, related to restricted stock units or restricted stock awards, recognized as expense or an asset, if compensation is capitalized.

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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.

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The total fair value of shares issued during the period under a deferred compensation arrangement.

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Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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

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No definition available.

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Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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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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Gross number of share options (or share units) granted during the period.

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No definition available.

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

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The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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Stock-Based Compensation - Narrative (Details)	12 Months Ended
Stock-Based Compensation - Narrative (Details)	Dec. 31, 2016 USD ($) director shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares	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
Total proceeds of the in-the-money options exercised	$ 142,000	$ 789,000	$ 442,000
Total intrinsic value of options exercised	11,000	220,000	178,000
Unrecognized compensation expense	0	0	0
Compensation expense related to stock options	$ 0	$ 0	$ 0
Stock options granted during period (in shares) \| shares	0	0	0
Regular quarterly retainer director could receive in cash	$ 5,800
Regular quarterly retainer if restricted stock vested	6,250
Monthly meeting fees a director could receive in cash	600
Monthly meeting fees a director could receive if restricted stock vested	$ 900
Number of directors elected to receive stock in lieu of cash \| director	11
Number of outside directors \| director	13
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as payment for deferred compensation (in shares) \| shares		4,158
Market value of shares issued as payment of deferred compensation		$ 95,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum vesting period of granted restricted stock	36 months
Unrecognized compensation cost	$ 568,000	340,000	$ 327,000
Share based compensation expense	$ 444,000	$ 322,000	$ 342,000
Number of shares issued (in shares) \| shares	13,166	11,228	13,147
Recognized share based compensation expense	$ 380,000	$ 275,000	$ 305,000
Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for recognition of unrecognized compensation cost	12 months
Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for recognition of unrecognized compensation cost	36 months