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Intangible Assets - Major Classes of Amortizable Intangible Assets (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, net	$ 3,584.6	$ 3,372.1
Expiration Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	7,052.3	6,472.3
Accumulated amortization	(3,543.9)	(3,178.5)
Amortizable intangible assets, net	3,508.4	3,293.8
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	102.9	91.3
Accumulated amortization	(74.1)	(67.5)
Amortizable intangible assets, net	28.8	23.8
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	108.6	108.5
Accumulated amortization	(61.2)	(54.0)
Amortizable intangible assets, net	$ 47.4	$ 54.5

X

- 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
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
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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
-Topic 928
-SubTopic 340
-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
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