Equity And Stock Based Compensation [Line Items]

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- Definition

Percentage Of Shares Vested

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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.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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

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

+ References

No definition available.

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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).

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Amount of stock repurchase plan authorized.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount remaining of a stock repurchase plan authorized.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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Shared-Based Compensation And Share Repurchase Plans (Narrative) (Details) - USD ($)			3 Months Ended	12 Months Ended
	Nov. 07, 2017	May 16, 2014	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Mar. 14, 2019	Sep. 30, 2017
Equity And Stock-Based Compensation [Line Items]
Unrecognized estimated compensation cost related to non-vested stock options granted				$ 881,000
Recognition period of unrecognized compensation cost				1 year 9 months 22 days
Proceeds from the exercise of stock option				$ 344,000	$ 52,000	$ 146,000
Stock Option [Member]
Equity And Stock-Based Compensation [Line Items]
Compensation expense				$ 425,000	310,000	284,000
Shares granted				126,840
Proceeds from the exercise of stock option				$ 361,000	574,000	$ 146,000
Restricted Stock Units (RSUs) [Member]
Equity And Stock-Based Compensation [Line Items]
Compensation expense				1,000,000	$ 668,000
Unrecognized estimated compensation cost related to non-vested stock options granted				$ 1,400,000
Shares granted				97,600
Restricted Stock Units (RSUs) [Member] \| Directors [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options and RSU				1 year
Percentage of shares vested				100.00%
Restricted Stock Units (RSUs) [Member] \| Management [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options and RSU					4 years
Percentage of shares vested				25.00%
2017 Stock Repurchase Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Stock buy-back program period				2 years
2014 Stock Repurchase Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase program, amount authorized		$ 10,000,000
Repurchase program, shares authorized		350,000
Share price		$ 11.74
Class A [Member]
Equity And Stock-Based Compensation [Line Items]
Shares granted				126,840	169,762	169,327
Class A [Member] \| James Cotter Jr. [Member]
Equity And Stock-Based Compensation [Line Items]
Stock options terminated				50,000
2010 Stock Incentive Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Additional shares authorized	947,460
Common Stock shares remaining for future issuances								302,540
Repurchase program, shares authorized								302,540
2010 Stock Incentive Plan [Member] \| Class A Nonvoting Common Stock [Member]
Equity And Stock-Based Compensation [Line Items]
Common Stock authorized for issuance under 2010 Stock Incentive Plan				1,250,000
Common Stock shares remaining for future issuances				1,031,970
2010 Stock Incentive Plan [Member] \| Class A [Member]
Equity And Stock-Based Compensation [Line Items]
Shares granted			0
2010 Stock Incentive Plan [Member] \| Minimum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options and RSU				0 years
2010 Stock Incentive Plan [Member] \| Maximum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options and RSU				4 years
Subsequent Event [Member] \| Class A [Member] \| 2017 Stock Repurchase Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase program, remaining amount authorized							$ 16,200,000