The percentage to retain annual restricted stock awards.

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
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- 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.

+ Details

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Balance Type:	na
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 16, 2013	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Stock Based Compensation [Abstract]
Stock-Based Compensation expense			$ 0	$ 0	$ 0
Increase in number of common stock shares authorized	233,334
Percentage to retain annual restricted stock awards	50.00%
Restricted Stock [Member]
Stock Based Compensation [Abstract]
Stock-Based Compensation expense		$ 532,000	571,000	1,656,000	1,675,000
Recognized tax benefits		$ 51,000	$ 66,000	$ 176,000	$ 191,000
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 \| 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
Class B Common Stock \| Incentive Compensation Plan [Member]
Stock Based Compensation [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	370,000