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Stock Plans - Options Vesting (Details) | 12 Months Ended
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Dec. 31, 2020
Monthly Percentage |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Percentage of awards vesting | 2.08%
Quarterly Percentage After First Anniversary |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Percentage of awards vesting | 6.25%
Upon Achievement of Performance Objectives |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Percentage of awards vesting | 33.33%
Annual Percentage After Achievement of Performance Objectives |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Percentage of awards vesting | 33.33%
2015 Plan | Stock options | First Anniversary |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Percentage of awards vesting | 25.00%
2010 Plan | Stock options | Second Anniversary |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Percentage of awards vesting | 50.00%
2000 and 2006 Stock incentive plans | Stock options | First Anniversary |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Percentage of awards vesting | 25.00%

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- Definition Percentage of vesting of award 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 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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