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Intangible Assets - Major Classes of Amortizable Intangible Assets (Detail) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
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Finite-Lived Intangible Assets [Line Items] |  |  |
Amortizable intangible assets, net | $ 2,318.7 | $ 1,773.0 | $ 1,644.6
Expiration Lists [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Amortizable intangible assets, gross | 4,246.0 | 3,379.4 |
Accumulated amortization | (2,004.3) | (1,676.8) |
Amortizable intangible assets, net | 2,241.7 | 1,702.6 |
Non-Compete Agreements [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Amortizable intangible assets, gross | 68.4 | 58.0 |
Accumulated amortization | (52.5) | (48.5) |
Amortizable intangible assets, net | 15.9 | 9.5 |
Trade Names [Member] |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Amortizable intangible assets, gross | 91.8 | 86.0 |
Accumulated amortization | (30.7) | (25.1) |
Amortizable intangible assets, net | $ 61.1 | $ 60.9 |

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- Definition Accumulated amount of 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 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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- 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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