Other Income, Net - Schedule of Components of Other Income (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Securities earnings:
Dividends and interest			$ 6.1	$ 16.8
Securities transactions, net			0.3
Security earnings, total	$ 3.3	$ 8.5	6.4	16.8
Currency transactions, net			(0.2)	4.8
Insurance recoveries	4.7	0.2	5.0	0.4
Infrastructure reimbursement			9.1	4.0
Gain on land sales			0.7	12.5
Other, net			1.0	1.2
Total	$ 15.4	$ 19.3	$ 22.0	$ 39.7

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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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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