Stock-Based Compensation (Summary Of Share-Based Transactions ) (Details) - Stock Option [Member] - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Number of Options, Oustanding	255,922
Number of Options, Granted	52,465
Number of Options, Expired	(2,080)
Number of Options, Cancelled	(101,733)
Number of Options, Oustanding	204,574	255,922
Weighted Average Exercise Price, Outstanding	$ 41.88
Weighted Average Exercise Price, Granted	6.41
Weighted Average Exercise price, Expired	97.78
Weighted Average Exercise Price, Cancelled	34.99
Weighted Average Exercise Price, Outstanding	$ 35.60	$ 41.88
Weighted Average Remaining Contractual Term, Outstanding	7 years 9 months 18 days	7 years 1 month 6 days
Number of Options, Exercisable	123,263
Weighted Average Exercise Price, Exercisable	$ 51.15
Weighted Average Remaining Contractual Term, Exercisable	6 years 2 months 12 days

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.

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 (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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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 grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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