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Goodwill and Identifiable Assets (Acquired Intangible Assets) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Intangible assets subject to amortization: |  |
Gross Carrying Amount | $ 603.3 | $ 603.6
Accumulated Amortization | 371.9 | 358.3
Net Carrying Amount | 231.4 | 245.3
Intangible assets not subject to amortization: |  |
Trademarks, Carrying Amount | 242.6 | 242.6
Intangible Assets, Gross (Excluding Goodwill) | 845.9 | 846.2
Intangible Assets, Net (Excluding Goodwill), Total | 474.0 | 487.9
Customer and Contractual Relationships |  |
Intangible assets subject to amortization: |  |
Accumulated Amortization | 272.0 | 260.2
Net Carrying Amount | 221.8 | 233.7
Total |  |
Other Finite-Lived Intangible Assets, Gross | $ 493.8 | 493.9
Customer and Contractual Relationships | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 7 years |
Customer and Contractual Relationships | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 13 years |
Contractor Relations |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 4 years |
Intangible assets subject to amortization: |  |
Accumulated Amortization | $ 45.4 | 45.5
Net Carrying Amount | 0.0 | 0.0
Total |  |
Other Finite-Lived Intangible Assets, Gross | 45.4 | 45.5
Backlog |  |
Intangible assets subject to amortization: |  |
Accumulated Amortization | 31.9 | 31.0
Net Carrying Amount | 2.8 | 3.8
Total |  |
Other Finite-Lived Intangible Assets, Gross | $ 34.7 | 34.8
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 | 3 years |
Noncompete Agreements |  |
Intangible assets subject to amortization: |  |
Accumulated Amortization | $ 22.6 | 21.6
Net Carrying Amount | 6.8 | 7.8
Total |  |
Other Finite-Lived Intangible Assets, Gross | $ 29.4 | $ 29.4
Noncompete Agreements | Minimum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 1 year |
Noncompete Agreements | Maximum [Member] |  |
Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 7 years |

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- Definition Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a projected indefinite period of benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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