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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
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

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 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
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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

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