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Equity Compensation Plans - Modifications to Stock-Based Awards (Details Textual) - Separation Agreement - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
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Aug. 31, 2020 | Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number | 198,000 |
Reversal of stock-based compensation expense |  | $ 2.7
Fair value of modified award recognized |  | $ 8.4

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- Definition Reversal of stock-based compensation expense. + References No definition available. + Details
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Balance Type: | credit
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- Definition Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement. + References No definition available. + Details
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Data Type: | xbrli:sharesItemType
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- Details
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