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Acquisitions Business Combinations Additional Information (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Acquired Indefinite-lived Intangible Assets [Line Items] |  |  |
Payments to Acquire Businesses, Net of Cash Acquired | $ 85.8 | $ 85.5 |
Business Acquisition, Goodwill, Expected Tax Deductible Amount | $ 51.3 |  |
2020 Acquisitions |  |  |
Acquired Indefinite-lived Intangible Assets [Line Items] |  |  |
Goodwill, Acquired During Period |  |  | $ 129.5

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