Consolidated Statements of Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net sales	$ 3,903.1	$ 3,696.0	$ 3,207.3
Cost of goods sold	3,267.7	3,173.2	2,728.6
Gross profit	635.4	522.8	478.7
Selling, general and administrative expenses	277.3	255.2	238.4
Operating income	358.1	267.6	240.3
Interest expense	(99.2)	(99.9)	(115.9)
Investment income	2.6	2.1	0.6
Other income (expense)
Debt refinancing and redemption costs	(0.8)	0.0	(36.8)
Other, net	12.0	6.9	(1.9)
Income before income taxes	272.7	176.7	86.3
Income tax expense (benefit)	37.1	33.7	(8.2)
Net income	$ 235.6	$ 143.0	$ 94.5
Basic earnings per share	$ 3.03	$ 1.85	$ 1.23
Diluted earnings per share	$ 3.02	$ 1.85	$ 1.23