Debt - Component of Debt (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Other indebtedness	$ 24.0	$ 25.6
Unamortized original issue discount and debt issuance costs	(66.7)	(70.2)
Debt	7,306.3	7,154.1
Less: current portion of long-term debt	320.0	76.3
Long-term debt	6,986.3	7,077.8
Secured Debt [Member] \| Senior Secured Credit Facilities [Member]
Debt Instrument [Line Items]
Long-term debt gross	5,103.0	5,198.7
Secured Debt [Member] \| Senior Secured Credit Facilities Revolving Portion [Member]
Debt Instrument [Line Items]
Long-term debt gross	246.0
Senior Notes [Member] \| 5.5% Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt gross	$ 2,000.0	$ 2,000.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt classified as other.

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