Percentage Of Shares Vested

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- Definition

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

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

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

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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

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.

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No definition available.

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- Definition

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

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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 stock repurchase plan authorized.

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No definition available.

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- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount remaining of a stock repurchase plan authorized.

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No definition available.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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- Definition

Amount allocated to previously issued common shares repurchased by the issuing entity and held in treasury.

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Share-Based Compensation And Share Repurchase Plans (Narrative) (Details) - USD ($)						3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 16, 2020	Dec. 16, 2020	Mar. 10, 2020	Mar. 05, 2020	May 07, 2019	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 14, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized estimated compensation cost related to non-vested stock options granted							$ 650,000,000,000	$ 650,000,000,000
Recognition period of unrecognized compensation cost								1 year 5 months 8 days
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense								$ 460,000	$ 458,000	$ 425,000
Proceeds from stock option exercises								$ 0	906,000	$ 361,000
Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock authorized for issuance							1,663,731	1,663,731
Class A [Member] \| 2020 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock authorized for issuance							1,250,000	1,250,000
Common Stock shares remaining for future issuances							1,096,394	1,096,394
Class A [Member] \| Maximum [Member] \| 2020 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized								1,024,902
Class B [Member] \| 2020 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock authorized for issuance							200,000	200,000
2017 Stock Repurchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase program, amount authorized			$ 25,000,000.0
Repurchase program, remaining amount authorized							$ 26,000,000.0	$ 26,000,000.0
Stock buy-back program period								2 years
2017 Stock Repurchase Plan [Member] \| Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase program, remaining amount authorized			$ 26,000,000.0
$25 Million Stock Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase program, amount authorized											$ 25,000,000.0
$25 Million Stock Repurchase Program [Member] \| Class A Nonvoting Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase value							$ 24,000,000.0	$ 24,000,000.0
Share price								$ 13.39
Shares repurchased plan, shares								1,792,819
$25 Million Stock Repurchased At $8.92 [Member] \| Class A Nonvoting Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price						$ 8.92
Shares repurchased plan, shares						75,157	0
$25 Million Stock Repurchased At $7.30 [Member] \| Class A Nonvoting Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price				$ 7.30
Shares repurchased plan, shares				25,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense					$ 35,000			$ 1,000,000.0	$ 1,000,000.0
Unrecognized estimated compensation cost related to non-vested stock options granted							$ 2,600,000	$ 2,600,000
Number of options, Granted								697,515
Management [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options and RSU								4 years
Percentage of shares vested								25.00%
Non-employee Director [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares vested								100.00%
Number of options, Granted	60,084
Executive Management And Other Employees [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options and RSU								1 year
Percentage of shares vested								100.00%
Number of options, Granted		114,803	287,163