Consolidated Statements of Income and Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net sales	$ 1,750.7	$ 1,809.9	$ 5,244.3	$ 5,268.1
Cost of sales	(1,339.3)	(1,366.7)	(3,983.6)	(4,048.2)
Gross profit	411.4	443.2	1,260.7	1,219.9
Selling, general and administrative expenses	(136.9)	(134.2)	(420.6)	(406.7)
Other expense, net	(11.7)	(10.5)	(21.5)	(32.2)
Income from operations	262.8	298.5	818.6	781.0
Non-operating pension expense	(1.9)	(0.5)	(6.0)	(1.6)
Interest expense, net	(21.6)	(23.9)	(68.0)	(73.4)
Income before taxes	239.3	274.1	744.6	706.0
Provision for income taxes	(59.5)	(67.4)	(184.4)	(172.6)
Net income	$ 179.8	$ 206.7	$ 560.2	$ 533.4
Net income per common share:
Basic	$ 1.90	$ 2.19	$ 5.93	$ 5.65
Diluted	1.89	2.18	5.91	5.64
Dividends declared per common share	$ 0.79	$ 0.79	$ 2.37	$ 2.21
Statements of Comprehensive Income:
Net income	$ 179.8	$ 206.7	$ 560.2	$ 533.4
Foreign currency translation adjustment				(0.1)
Reclassification adjustments to cash flow hedges included in net income, net of tax of $0.3 million, $0.3 million, $1.0 million, and $1.0 million	1.0	1.0	2.9	3.0
Amortization of pension and postretirement plans actuarial loss and prior service cost, net of tax of $0.8 million, $1.0 million, $2.4 million, and $3.0 million	2.4	3.0	7.1	8.9
Other comprehensive income	3.4	4.0	10.0	11.8
Comprehensive income	$ 183.2	$ 210.7	$ 570.2	$ 545.2