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Deferred Revenue and Performance Obligation (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Deferred Revenue and Performance Obligation [Abstract] |  |  |  |
Deferred Revenue, Revenue Recognized | $ 43.3 | $ 45.3 | $ 86.0 | $ 107.2
Revenue, Remaining Performance Obligation, Amount | 373.0 |  | 373.0 |
Revenue Remaining Performance Obligation, to be recognized within 12 months | $ 180.5 |  | $ 180.5 |

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- Definition Deferred Revenue and Performance Obligation [Abstract] + References No definition available. + Details
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- Definition Revenue Remaining Performance Obligation, to be recognized within 12 months + References No definition available. + Details
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- Definition Amount of revenue recognized that was previously reported as deferred or unearned revenue. + References No definition available. + Details
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- Definition Amount of transaction price allocated to performance obligation that has not been recognized as revenue. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130556-203045 + Details
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