Equity And Stock Based Compensation [Line Items]

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- Definition

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

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- Definition

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

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- Definition

Share-based compensation arrangement by share based payment award realized value of option exercised.

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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-Publisher FASB

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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

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

Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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- Definition

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

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- Definition

Number of share options (or share units) exercised during the current 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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- Definition

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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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Equity And Stock-Based Compensation (Narrative) (Details) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2015	Sep. 30, 2014	May. 16, 2014	May. 14, 2004
Equity And Stock-Based Compensation [Line Items]
Grant date fair value of options vesting	$ 75,428			$ 34,000			$ 208,831	$ 102,000
Unrecognized estimated compensation cost related to non-vested stock options granted	653,626						$ 653,626
Recognition period of unrecognized compensation cost							1 year 10 months 10 days
Intrinsic unrealized value of all options outstanding, vested and expected to vest	2,300,000						$ 2,300,000
Percentage of option currently exercisable							58.30%
May 2014 Stock Repurchase Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Stock Repurchase Program, Authorized Amount									$ 10,000,000
Repurchase program, shares authorized										350,000
Repurchased program, amount repurchased							$ 7,200,000
Repurchase program, average price per share							$ 12.92
Repurchase program, remaining amount authorized	$ 2,800,000						$ 2,800,000
Class A Nonvoting Common Stock [Member]
Equity And Stock-Based Compensation [Line Items]
Stock issued	0	0		0	0
Options exercised							336,100
Common Stock authorized for issuance under 2010 Stock Incentive Plan	1,250,000						1,250,000
Common Stock shares remaining for future issuances	663,800						663,800
Class A Nonvoting Common Stock [Member] \| Executive Officer [Member]
Equity And Stock-Based Compensation [Line Items]
Stock issued			160,643			125,209
Class A Nonvoting Common Stock [Member] \| Employee/Director [Member]
Equity And Stock-Based Compensation [Line Items]
Realized value of option exercised							$ 1,700,000
Cash received from exercise of stock options							$ 2,700,000
Minimum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options							0 years
Maximum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options							4 years