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Intangible Assets - Major Classes of Amortizable Intangible Assets (Detail) - USD ($) $ in Millions | Jun. 30, 2020 | Dec. 31, 2019
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Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, net | $ 2,226.0 | $ 2,318.7
Expiration Lists [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, gross | 4,342.8 | 4,246.0
Accumulated amortization | (2,203.2) | (2,004.3)
Amortizable intangible assets, net | 2,139.6 | 2,241.7
Non-Compete Agreements [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, gross | 67.0 | 68.4
Accumulated amortization | (54.0) | (52.5)
Amortizable intangible assets, net | 13.0 | 15.9
Trade Names [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Amortizable intangible assets, gross | 107.2 | 91.8
Accumulated amortization | (33.8) | (30.7)
Amortizable intangible assets, net | $ 73.4 | $ 61.1

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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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