Consolidated Statements of Income and Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Net sales	$ 2,182.4	$ 1,936.0	$ 6,237.2	$ 5,864.5
Cost of sales	(1,677.2)	(1,523.3)	(4,923.8)	(4,575.7)
Gross profit	505.2	412.7	1,313.4	1,288.8
Selling, general and administrative expenses	(162.0)	(144.2)	(463.3)	(438.1)
Other expense, net	(16.1)	(9.9)	(51.0)	(37.1)
Income from operations	327.1	258.6	799.1	813.6
Non-operating pension income (expense)	1.2	(1.8)	3.4	(5.8)
Interest expense, net	(9.7)	(12.3)	(29.7)	(42.2)
Income before taxes	318.6	244.5	772.8	765.6
Provision for income taxes	(80.5)	(61.3)	(188.8)	(189.6)
Net income	$ 238.1	$ 183.2	$ 584.0	$ 576.0
Net income per common share:
Basic	$ 2.65	$ 2.04	$ 6.51	$ 6.41
Diluted	2.64	2.03	6.48	6.38
Dividends declared per common share	$ 1.25	$ 1.25	$ 3.75	$ 3.75
Statements of Comprehensive Income:
Net Income (Loss)	$ 238.1	$ 183.2	$ 584.0	$ 576.0
Changes in unrealized gains on marketable debt securities, net of tax of ($0.3) million, ($0.1) million, ($0.3) million, and ($0.3) million, respectively	1.0	0.4	0.8	0.9
Amortization of pension and postretirement plans actuarial loss and prior service cost, net of tax of ($0.4) million, ($0.5) million, ($1.0) million, and ($1.6) million, respectively	1.0	1.6	3.1	4.8
Other comprehensive income	2.0	2.0	3.9	5.7
Comprehensive income	$ 240.1	$ 185.2	$ 587.9	$ 581.7