Equity And Stock Based Compensation [Line Items]

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- Definition

Percentage Of Shares Vested

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- Definition

Share-based compensation arrangement by share-based payment award options vested grant date fair value.

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No definition available.

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- Definition

Share-based compensation arrangement byshare-based payment award percentage of options exercisable.

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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

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 difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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

+ References

No definition available.

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Amount of stock repurchase plan authorized.

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- Definition

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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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

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

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- Definition

Amount allocated to previously issued common shares repurchased by the issuing entity and held in treasury.

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Stock-Based Compensation And Stock Repurchases (Narrative) (Details) - USD ($)			3 Months Ended		12 Months Ended
	May 07, 2019	Nov. 07, 2017	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Sep. 30, 2017	Mar. 02, 2017	Dec. 31, 2016
Equity And Stock-Based Compensation [Line Items]
Repurchase program, amount authorized			$ 16,200,000
Shares granted			219,408
Stock Option [Member]
Equity And Stock-Based Compensation [Line Items]
Grant date fair value of options vesting			$ 70,000	$ 85,000
Unrecognized estimated compensation cost related to non-vested stock options granted			$ 1,500,000
Recognition period of unrecognized compensation cost			2 years 1 month 10 days
Percentage of option currently exercisable			91.00%
Intrinsic unrealized value of all options outstanding, vested and expected to vest			$ 2,000,000
Restricted Stock Units (RSUs) [Member]
Equity And Stock-Based Compensation [Line Items]
Compensation expense			209,000	$ 294,000
Unrecognized estimated compensation cost related to non-vested stock options granted			$ 1,900,000
Vesting period of stock options and RSU			1 year 1 month 6 days
Restricted Stock Units (RSUs) [Member] \| Directors [Member]
Equity And Stock-Based Compensation [Line Items]
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
$25 Million Stock Repurchase Program [Member]
Equity And Stock-Based Compensation [Line Items]
Share price			$ 16.20
Shares repurchased plan, shares			566
Class A Nonvoting Common Stock [Member]
Equity And Stock-Based Compensation [Line Items]
Common Stock authorized for issuance under 2010 Stock Incentive Plan			2,197,460
Class A [Member]
Equity And Stock-Based Compensation [Line Items]
Shares granted			219,408		126,840
Class A [Member] \| 2017 Stock Repurchase Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase program, amount authorized			$ 16,200,000
Class A [Member] \| $25 Million Stock Repurchase Program [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase value			$ 8,800,000
Repurchase program, amount authorized							$ 25,000,000
Share price			$ 15.81
Shares repurchased plan, shares			559,627
Minimum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options and RSU			0 years
Maximum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options and RSU			4 years
2010 Stock Incentive Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Additional shares authorized		947,460
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			789,869
Repurchase program, shares available						302,540
Subsequent Event [Member] \| Restricted Stock Units (RSUs) [Member]
Equity And Stock-Based Compensation [Line Items]
Compensation expense	$ 35,000