Equity And Stock Based Compensation [Line Items]

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- Definition

Percentage Of Shares Vested

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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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
-SubTopic 10
-Section 50
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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

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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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

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.

+ References

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

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
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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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- Definition

Number of shares of common stock subject to repurchase or cancellation determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period. Common stock subject to repurchase are outstanding common shares that are contingently returnable (that is, subject to recall).

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Stock-Based Compensation and Stock Repurchases (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 02, 2017	Dec. 31, 2016
Stock Option [Member]
Equity And Stock-Based Compensation [Line Items]
Grant date fair value of options vesting	$ 86,000	$ 74,000	$ 223,000	$ 264,000
Unrecognized estimated compensation cost related to non-vested stock options granted	915,000		$ 915,000
Recognition period of unrecognized compensation cost			1 year 11 months 5 days
Intrinsic unrealized value of all options outstanding, vested and expected to vest	3,000,000		$ 3,000,000
Percentage of option currently exercisable			79.50%
Restricted Stock Units (RSUs) [Member]
Equity And Stock-Based Compensation [Line Items]
Compensation expense	182,000	$ 130,000	$ 482,000	$ 290,000
Unrecognized estimated compensation cost related to non-vested stock options granted	1,000,000		$ 1,000,000
Vesting period of stock options and RSU			1 year
Restricted Stock Units (RSUs) [Member] \| Director [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%
May 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]
Repurchase value	6,400,000		$ 6,400,000
Repurchase program, remaining amount authorized	$ 18,600,000		$ 18,600,000
Share price			$ 15.92
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		1,250,000
Class A [Member]
Equity And Stock-Based Compensation [Line Items]
Weighted average number of common stocks - repurchased	192,207		403,156
Class A [Member] \| $25 Million Stock Repurchase Program [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase program, amount authorized					$ 25,000,000
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