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]
Discontinued operations, net of income taxes	$ (33.5)	$ (21.3)	$ (18.1)	$ 9.6	$ (122.1)	$ 23.9	$ 32.7	$ 39.4	$ (63.3)	$ (26.1)	$ 671.5
Costs of sales and services									(2,526.2)	(2,405.5)	(1,579.4)
Selling, general and administrative expenses									(792.9)	(790.0)	(581.7)
Income (loss) from continuing operations before income taxes									655.0	608.4	95.8
Provision for income taxes									(111.5)	(70.8)	(228.9)
Net income (loss)	$ (2.8)	$ 89.5	$ 176.3	$ 217.2	$ 34.6	$ 74.8	$ 132.5	$ 269.6	480.2	511.5	538.4
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)									(1.7)	(8.8)	(64.8)
Reclassification out of Accumulated Other Comprehensive Income | Foreign Currency translation adjustments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Discontinued operations, net of income taxes									0.0	0.0	(13.9)
Reclassification out of Accumulated Other Comprehensive Income | Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before income taxes									11.2
Provision for income taxes									(3.0)
Net income (loss)									8.2
Reclassification out of Accumulated Other Comprehensive Income | Derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before income taxes										10.5	0.8
Provision for income taxes										(2.8)	(0.1)
Net income (loss)										7.7	0.7
Reclassification out of Accumulated Other Comprehensive Income | Amortization of prior service costs
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses									(0.3)	(0.3)	(0.5)
Reclassification out of Accumulated Other Comprehensive Income | Amortization of unrecognized net actuarial and other gains (losses)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses									(10.8)	(14.4)	(14.4)
Reclassification out of Accumulated Other Comprehensive Income | Recognized loss due to settlement/curtailment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Discontinued operations, net of income taxes									(1.4)	(6.1)	(51.2)
Reclassification out of Accumulated Other Comprehensive Income | Pension and other postretirement benefits
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total income (loss) from discontinued operations, before tax									(12.5)	(20.8)	(66.1)
Provision for income taxes									2.6	4.3	14.5
Net income (loss)									(9.9)	(16.5)	(51.6)
Reclassification out of Accumulated Other Comprehensive Income | Foreign currency contracts | Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Costs of sales and services									10.0
Selling, general and administrative expenses									1.9
Reclassification out of Accumulated Other Comprehensive Income | Foreign currency contracts | Derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Costs of sales and services										18.9	(10.0)
Selling, general and administrative expenses										(8.0)	10.0
Reclassification out of Accumulated Other Comprehensive Income | Energy contracts | Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Costs of sales and services									0.0
Reclassification out of Accumulated Other Comprehensive Income | Energy contracts | Derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Costs of sales and services										0.0	0.8
Reclassification out of Accumulated Other Comprehensive Income | Interest rate contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense									$ (0.7)	$ (0.4)	$ 0.0