Investments in Affiliates and Other Related Party Transactions - Summarized Balance Sheet Data for Affiliates Accounted for under Equity Method (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Balance sheet data:
Current assets	$ 856.3	$ 753.8
Non-current assets	173.9	180.8
Current liabilities	739.5	679.3
Non-current liabilities	$ 6.6	$ 6.3

Equity Method Investment, Summarized Financial Information, Balance Sheet [Abstract]

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The amount of current assets reported by an equity method investment of the entity.

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