The percentage to retain annual restricted stock awards.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

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

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- Definition

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

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No definition available.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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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

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

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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Stock-Based Compensation (Narrative) (Details) - USD ($)	1 Months Ended	12 Months Ended
	Oct. 16, 2013	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Based Compensation [Abstract]
Stock options granted		0	0	0
Stock options outstanding		0	0	0
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
Weighted average grant date fair value of restricted stock that vested during			$ 2,276,000	$ 2,385,000
Net value of unrecognized compensation cost related to unvested restricted stock awards		$ 1,896,000	4,195,000	4,166,000
Restricted Stock [Member]
Stock Based Compensation [Abstract]
Stock-Based Compensation expense		$ 2,221,000	$ 2,129,000	$ 2,201,000
Shares, Granted		0	72,985	63,811
Recognized tax benefits		$ 235,000	$ 227,000	$ 251,000
Stock Option [Member]
Stock Based Compensation [Abstract]
Stock-Based Compensation expense		$ 0	$ 0	$ 0
Class A Common Stock \| Stock Option [Member]
Stock Based Compensation [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	990,000
Class A Common Stock \| Convert For Class B [Member]
Stock Based Compensation [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	370,000
Class A Common Stock \| Incentive Compensation Plan [Member]
Stock Based Compensation [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	620,000
Class B Common Stock
Stock Based Compensation [Abstract]
Increase in number of common stock shares authorized	90,000
Class B Common Stock \| Stock Option [Member]
Stock Based Compensation [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	370,000