Stock Compensation (Schedule of Share Based Compensation Stock Options Activities) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Stock Compensation [Abstract]
Beginning Outstanding, Number of Shares	1,981
Granted - Number of Shares	557
Exercised - Number of Shares	(9)
Forfeited - Number of Shares	(63)
Expired - Number of Shares	(20)
Ending Outstanding, Number of Shares	2,446	1,981
Expected to vest - Number of shares	1,256
Exercisable - Number of Shares	1,190
Beginning Outstanding, Weighted Average Exercise Price	$ 99.87
Granted - Weighted Average Exercise Price	99.94
Exercised - Weighted Average Exercise Price	47.78
Forfeited - Weighted Average Exercise Price	97.85
Expired - Weighted Average Exercise Price	198.78
Ending Outstanding, Weighted Average Exercise Price	99.32	$ 99.87
Expected to vest - Weighted Average Exercise Price	92.39
Exercisable - Weighted Average Exercise Price	$ 106.62
Options Outstanding - Weighted Average Remaining Life	7 years 8 months 12 days	7 years 4 months 24 days
Expected to vest - Weighted Average Remaining Term	9 years
Exercisable - Weighted Average Remaining Term	6 years 4 months 24 days
Options Outstanding - Aggregate Intrinsic Value	$ 6,106	$ 65,662
Expected to vest - Aggregate Intrinsic Value	1,005
Exercisable - Aggregate Intrinsic Value	$ 5,101

Share based compensation arrangement by share based payment award options expirations only in period.

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Share based compensation arrangement by share based payment award options expirations only in period weighted average exercise price.

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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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. 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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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. 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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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. 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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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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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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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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.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. 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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Number of share options (or share units) exercised during the current period.

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