Describes the stock options exercise price.

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
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-Publisher FASB
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-Topic 718
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-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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=120381028&loc=d3e5070-113901

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Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ 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
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-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Period Type:	instant

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- Details

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- Details

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Stock-Based Compensation (Narrative) (Details) - USD ($)		3 Months Ended		12 Months Ended
	Oct. 16, 2013	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Stock Based Compensation [Abstract]
Stock-Based Compensation expense		$ 0	$ 0
Stock options granted		0		0
Stock options outstanding		0
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
Restricted Stock [Member]
Stock Based Compensation [Abstract]
Stock-Based Compensation expense		$ 339,000	343,000
Recognized tax benefits		$ 37,000	$ 30,000
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 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 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