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Goodwill and Other Intangible Assets - Summary of the Acquisition Date Fair Values of Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions | Apr. 27, 2021 | Jan. 01, 2021 | Jul. 02, 2020 | Apr. 07, 2020
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Kingsbridge Group Limited | Specialty Insurance Distribution (NSM) |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill and intangible assets acquired |  |  |  | $ 131.7
Ark | Specialty Insurance Distribution (NSM) |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill and intangible assets acquired |  | $ 292.5 |  |
Other |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill and intangible assets acquired | $ 31.0 |  | $ 31.0 |

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