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Intangible Assets - Major Classes of Amortizable Intangible Assets (Detail) - USD ($) $ in Millions | Mar. 31, 2022 | Dec. 31, 2021
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Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, net | $ 3,877.6 | $ 3,954.0
Expiration Lists [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, gross | 6,749.3 | 6,696.8
Accumulated amortization | (2,941.1) | (2,812.2)
Amortizable intangible assets, net | 3,808.2 | 3,884.6
Non-Compete Agreements [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, gross | 78.5 | 76.0
Accumulated amortization | (64.4) | (62.8)
Amortizable intangible assets, net | 14.1 | 13.2
Trade Names [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, gross | 106.1 | 105.2
Accumulated amortization | (50.8) | (49.0)
Amortizable intangible assets, net | $ 55.3 | $ 56.2

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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 928 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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