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Stockholders' Equity and Stock Plans - Cashless Exercise Information (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Equity [Abstract] |  |  |
Number of shares withheld (in shares) | 10,001 | 7,795 | 46,794
Total amount withheld (in thousands) | $ 398 | $ 326 | $ 1,698
Weighted-average price (usd per share) | $ 39.83 | $ 41.84 | $ 36.28

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- Definition Adjustments Related To Tax Withholding And Exercise Of Options For Share-Based Compensation + References No definition available. + Details
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- Definition Share-based Compensation Arrangements by Share-based Payment Award, Options, Tax Withholding And Exercises in Period, Weighted Average Exercise Price + References No definition available. + Details
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- References No definition available. + Details
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- Definition Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement. + References No definition available. + Details
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