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v3.20.2

Goodwill and Identifiable Assets (Acquired Intangible Assets) (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 583.0 | $ 524.7
Accumulated Amortization | 345.1 | 307.1
Net Carrying Amount | 237.9 | 217.6
Intangible assets not subject to amortization: |  |
Trademarks, Carrying Amount | 258.9 | 258.9
Intangible Assets, Gross (Excluding Goodwill) | 841.9 | 783.6
Intangible Assets, Net (Excluding Goodwill), Total | 496.8 | 476.5
Customer and Contractual Relationships |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | 437.3 | 384.9
Accumulated Amortization | 211.2 | 179.9
Net Carrying Amount | $ 226.1 | 205.0
Customer and Contractual Relationships | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 2 years |
Customer and Contractual Relationships | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 12 years 9 months |
Contractor Relations |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 71.1 | 71.1
Accumulated Amortization | 70.9 | 70.6
Net Carrying Amount | $ 0.2 | 0.5
Contractor Relations | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 2 years |
Contractor Relations | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 5 years |
Backlog |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 28.3 | 25.0
Accumulated Amortization | 27.1 | 23.9
Net Carrying Amount | $ 1.2 | 1.1
Backlog | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 1 year |
Backlog | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 2 years 9 months |
Noncompete Agreements |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 27.4 | 24.8
Accumulated Amortization | 17.0 | 13.8
Net Carrying Amount | $ 10.4 | 11.0
Noncompete Agreements | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 2 years |
Noncompete Agreements | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 7 years |
In-use software |  |
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 18.9 | 18.9
Accumulated Amortization | 18.9 | 18.9
Net Carrying Amount | $ 0.0 | $ 0.0
In-use software | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 6 years |

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