The percentage to retain annual restricted stock awards.

No definition available.

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- Definition

Describes the stock options exercise price.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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-Publisher FASB
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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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.

+ References

No definition available.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

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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-Publisher FASB
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Stock-Based Compensation (Details Textual) - USD ($)	1 Months Ended	12 Months Ended
Stock-Based Compensation (Details Textual) - USD ($)	Oct. 16, 2013	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of common stock shares authorized	233,334
Percentage to retain annual restricted stock awards	50.00%
Stock options exercise price description	may not be exercised at a price which is less than 100% of the fair market value of shares at the date of grant
Intrinsic value of stock options exercised		$ 0	$ 0	$ 664,321
Proceeds from stock options exercised		0	0	354
Weighted average grant date fair value of restricted stock that vested during		2,276,000	2,385,000	2,300,000
Net value of unrecognized compensation cost related to unvested restricted stock awards		4,195,000	4,166,000	4,063,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation expense		2,129,000	2,201,000	2,279,000
Recognized tax benefits		$ 227,000	$ 251,000	$ 912,000
Class A Common Stock \| Convert For Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	370,000
Class A Common Stock \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	990,000
Class A Common Stock \| Incentive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	620,000
Class B Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of common stock shares authorized	90,000
Class B Common Stock \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	370,000