Equity And Stock Based Compensation [Line Items]

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Percentage Of Shares Vested

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Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Vested And Nonvested, Outstanding, Number

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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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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

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

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

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

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

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No definition available.

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Amount of stock repurchase plan authorized.

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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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Amount remaining of a stock repurchase plan authorized.

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

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

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Stock-Based Compensation And Stock Repurchases (Narrative) (Details) - USD ($)		3 Months Ended		12 Months Ended
	Aug. 07, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Mar. 10, 2020	Mar. 02, 2017
Equity And Stock-Based Compensation [Line Items]
Common Stock authorized for issuance under 2010 Stock Incentive Plan		1,676,163
Shares granted			219,408
Stock Option [Member]
Equity And Stock-Based Compensation [Line Items]
Compensation expense		$ 120,000	$ 70,000
Unrecognized estimated compensation cost related to non-vested stock options granted		$ 1,000,000
Recognition period of unrecognized compensation cost		1 year 8 months 9 days
Share price		$ 3.89
Intrinsic unrealized value of all options outstanding, vested and expected to vest
Restricted Stock Units (RSUs) [Member]
Equity And Stock-Based Compensation [Line Items]
Compensation expense	$ 35,000	216,000	$ 209,000
Unrecognized estimated compensation cost related to non-vested stock options granted		$ 2,700,000
Vesting period of stock options and RSU		2 years 1 month 13 days
Percentage of shares vested		100.00%
Number of options, Grants		566,680
Restricted Stock Units (RSUs) [Member] \| Directors [Member]
Equity And Stock-Based Compensation [Line Items]
Number of options, Grants		129,796
Restricted Stock Units (RSUs) [Member] \| Management [Member]
Equity And Stock-Based Compensation [Line Items]
Percentage of shares vested		25.00%
Number of options, Grants		436,884
2017 Stock Repurchase Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase program, amount authorized					$ 25,000,000
Repurchase program, remaining amount authorized		$ 26,000,000
Stock buy-back program period		2 years
Class A Nonvoting Common Stock [Member]
Equity And Stock-Based Compensation [Line Items]
Common Stock authorized for issuance under 2010 Stock Incentive Plan		2,197,460
Class A Nonvoting Common Stock [Member] \| $25 Million Stock Repurchase Program [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase value		$ 24,000,000
Share price		$ 13.39
Shares repurchased plan, shares		1,792,819
Class A Nonvoting Common Stock [Member] \| $25 Million Stock Repurchased At $8.92 [Member]
Equity And Stock-Based Compensation [Line Items]
Share price		$ 8.92
Shares repurchased plan, shares		75,157
Class A [Member]
Equity And Stock-Based Compensation [Line Items]
Share price		$ 8.92
Shares granted				219,408
Shares repurchased plan, shares		75,157
Forfeiture of shares		8,000		25,000
Class A [Member] \| 2017 Stock Repurchase Plan [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase program, remaining amount authorized					$ 26,000,000
Class A [Member] \| $25 Million Stock Repurchase Program [Member]
Equity And Stock-Based Compensation [Line Items]
Repurchase program, amount authorized						$ 25,000,000
2010 Stock Incentive Plan [Member] \| Class A Nonvoting Common Stock [Member]
Equity And Stock-Based Compensation [Line Items]
Common Stock shares remaining for future issuances		521,297