Other Income, Net - Schedule of Components of Other Income (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Securities earnings:
Dividends and interest	$ 2.9	$ 8.3
Securities transactions, net	0.2
Security earnings, total	3.1	8.3
Currency transactions, net	0.9	(5.0)
Insurance recoveries	0.3	0.2
Infrastructure reimbursement	1.1	3.8
Gain on land sales		12.5
Other, net	1.2	0.6
Total	$ 6.6	$ 20.4

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

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Amount of revenue and income classified as other.

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Infrastructure development cost reimbursed.

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Aggregate nonoperating income amounts earned from investment securities including dividends, interest on securities, profits (losses) on securities and net and miscellaneous other income items.

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