Stockholders’ Equity - Components of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 5,253.2	$ 14,181.3	$ 11,384.4
Other comprehensive income (loss) before reclassifications	(17.7)	(159.3)
Amounts reclassified to earnings	10.6	72.2
Total other comprehensive income (loss), net of tax	(7.1)	(87.1)	281.7
Reclassification to retained earnings		(62.6)
Ending balance	4,996.0	5,253.2	14,181.3
Cumulative Translation Adjustment
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(492.6)	(318.8)
Other comprehensive income (loss) before reclassifications	4.4	(203.0)
Amounts reclassified to earnings	9.7	29.2
Total other comprehensive income (loss), net of tax	14.1	(173.8)
Reclassification to retained earnings		0.0
Ending balance	(478.5)	(492.6)	(318.8)
Pension and Postretirement Costs
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(398.1)	(385.5)
Other comprehensive income (loss) before reclassifications	(8.0)	29.1
Amounts reclassified to earnings	7.1	12.8
Total other comprehensive income (loss), net of tax	(0.9)	41.9
Reclassification to retained earnings		(54.5)
Ending balance	(399.0)	(398.1)	(385.5)
Derivative Financial Instruments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(22.1)	(58.8)
Other comprehensive income (loss) before reclassifications	(14.1)	14.6
Amounts reclassified to earnings	(6.2)	30.2
Total other comprehensive income (loss), net of tax	(20.3)	44.8
Reclassification to retained earnings		(8.1)
Ending balance	(42.4)	(22.1)	(58.8)
AOCL
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(912.8)	(763.1)	(1,044.8)
Ending balance	$ (919.9)	$ (912.8)	$ (763.1)

Amount after tax, of reclassification from AOCI to retained earnings related to the Tax Cuts and Jobs Act of 2017.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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