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Stock Plans - Stock-Based Compensation Expense (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Restricted stock and stock units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Total unrecognized compensation cost, net of estimated forfeitures | $ 75.3 | $ 73.9 | $ 71.6

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- Definition Amount, after tax, of expense for award under share-based payment arrangement. + References No definition available. + Details
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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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- Details
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