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Stock Plans and Share-Based Compensation - Shares Issued Under Employee Stock Purchase Plan (Details) - ESPP - Employee Stock Purchase Plan - $ / shares shares in Thousands | 6 Months Ended
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Jun. 30, 2021 | Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares issued (in shares) | 396 | 366
Weighted average purchase price per share (in dollars per share) | $ 19.33 | $ 20.50

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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Issued + 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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- Definition Number of shares issued under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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