Stockholders' Equity (Information Relating to Option Grants and Exercises) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stockholders' Equity
Weighted-average grant date fair value (in Dollars per share)	$ 7.15	$ 8.17	$ 5.48	$ 8.46
Intrinsic value of options exercised	$ 6,486	$ 452	$ 6,974	$ 5,822
Cash received	19,088	1,108	20,339	5,047
Total fair value of the options vested during the year	$ 2,411	$ 388	$ 9,844	$ 7,502

Amount of cash inflow from exercise of option under share-based payment arrangement.

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-Name Accounting Standards Codification
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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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