Stockholders' Equity And Stock-Based Compensation (Summary Of Stock Warrant Activity) (Details)	6 Months Ended
Jun. 30, 2021 $ / shares shares
Stockholders' Equity And Stock-Based Compensation [Abstract]
Beginning Balance, Number of shares	5,039,194
Options granted, Number of shares	976,078
Options exercised, Number of shares	(44,981)
Options canceled, Number of shares	(80,029)
Options expired, Number of shares	(62,738)
Ending Balance, Number of shares	5,827,524
Beginning Balance, Weighted average exercise price per share \| $ / shares	$ 14.26
Ending Balance, Weighted average exercise price per share \| $ / shares	$ 15.64

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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Number of share options (or share units) exercised during the current period.

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