Stockholders' Equity (Reclassification Out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenues		$ (3,726.8)	$ (3,335.1)	$ (3,434.2)	$ (2,913.0)	$ (3,323.0)	$ (3,143.8)	$ (2,960.9)	$ (3,125.2)	$ (13,409.1)	$ (12,552.9)	$ (15,056.9)
Selling, general and administrative expense										(1,228.1)	(1,140.6)	(1,060.9)
Other income (expense), net										(220.7)	(323.9)	(25.9)
Income (loss) before income taxes	[1]									(2,135.8)	(1,488.1)	679.7
Provision (benefit) for income taxes										276.3	422.7	545.5
Net income		$ (2,430.3)	$ (115.3)	$ 113.7	$ 19.8	$ (2,246.5)	$ 134.2	$ 110.1	$ 91.4	(2,412.1)	(1,910.8)	134.2
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Provision (benefit) for income taxes										(0.8)	0.1
Accumulated Foreign Currency Adjustment Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income (expense), net										12.0	41.1
Defined pension and other post-retirement benefits | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) before income taxes										(3.8)	1.1	21.8
Provision (benefit) for income taxes												9.1
Net income										(3.0)	1.0	12.7
Settlements and curtailments										0.3	(3.0)	25.3
Amortization of actuarial gain (loss)										2.5	0.6	2.5
Amortization of prior service credit (cost)										(1.0)	(1.3)	(1.0)
Foreign exchange contract | Hedging | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income										(18.2)	2.0	(101.2)
International | Pensions
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Settlements and curtailments										0.3	(3.4)	1.5
Amortization of actuarial gain (loss)										0.7	0.6	2.5
Amortization of prior service credit (cost)										(1.0)	(1.3)	(1.0)
Cash flow hedging | Foreign exchange contract | Hedging | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenues										26.6	2.4	39.3
Costs of sales										12.0	3.4	5.3
Selling, general and administrative expense										0.0	(0.1)	0.8
Other income (expense), net										(9.1)	1.0	(102.2)
Income (loss) before income taxes										(23.7)	1.9	(135.4)
Provision (benefit) for income taxes										$ (5.5)	$ (0.1)	$ (34.2)

[1] Includes amounts attributable to noncontrolling interests.