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Intangible Assets - Major Classes of Amortizable Intangible Assets (Detail) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
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Finite-Lived Intangible Assets [Line Items] |  |  |  |
Amortizable intangible assets, net | $ 1,773.0 | $ 1,644.6 | [1] | $ 1,627.3
Expiration Lists [Member] |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Amortizable intangible assets, gross | 3,379.4 | 3,055.9 |  |
Accumulated amortization | (1,676.8) | (1,422.1) |  |
Amortizable intangible assets, net | 1,702.6 | 1,633.8 |  |
Non-Compete Agreements [Member] |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Amortizable intangible assets, gross | 58.0 | 53.5 |  |
Accumulated amortization | (48.5) | (46.1) |  |
Amortizable intangible assets, net | 9.5 | 7.4 |  |
Trade Names [Member] |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Amortizable intangible assets, gross | 86.0 | 25.9 |  |
Accumulated amortization | (25.1) | (22.5) |  |
Amortizable intangible assets, net | $ 60.9 | $ 3.4 |  |
[1] | See Note 3 - Revenues from Contracts with Customers for additional information about the restatements related to Topic 606.

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