Shareholders' Equity And Stock-Based Compensation (Summary Of Stock Option Activity) (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding	907,000
Number of Shares, Awards granted	73,000
Number of Shares, Awards exercised or released	(84,000)
Number of Shares, Outstanding	896,000
Number of Shares, Exercisable	659,000
Number of Shares, Available for future grant at beginning of period	73,000
Number of Shares, Available for future grant at end of period	20,000
Weighted-average Exercise Price, Outstanding \| $ / shares	$ 6.51
Weighted-average Exercise Price, Awards exercised or released \| $ / shares	5.26
Weighted-average Exercise Price, Outstanding \| $ / shares	6.57
Weighted-average Exercise Price, Exercisable \| $ / shares	$ 6.57
Aggregate Intrinsic Value, Outstanding \| $	$ 19,045
Aggregate Intrinsic Value, Exercisable \| $	$ 12,572
Additional number of shares authorized	500,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding	690,000
Number of Shares, Awards granted	0
Number of Shares, Awards exercised or released	(31,000)
Number of Shares, Outstanding	659,000
Number of Shares, Exercisable	659,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Outstanding	217,000
Number of Shares, Awards granted	73,000
Number of Shares, Awards exercised or released	(53,000)
Number of Shares, Outstanding	237,000

Share-based Compensation Arrangement by Share-based Payment Award, Additional Number of Shares Authorized

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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Number of share options (or share units) exercised during the current period.

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