Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Net sales	$ 2,009.2	$ 2,584.6	$ 4,220.4	$ 4,744.6
Cost of goods sold (exclusive of depreciation)	1,520.1	2,007.3	3,198.7	3,670.9
Operating expenses:
Outbound freight and handling	80.7	95.4	172.2	178.3
Warehousing, selling and administrative	245.5	280.8	525.0	534.2
Other operating expenses, net	43.6	63.8	47.7	228.6
Depreciation	40.4	39.7	82.1	72.9
Amortization	14.8	18.6	30.6	33.0
Impairment charges	16.9	0.0	16.9	0.0
Total operating expenses	441.9	498.3	874.5	1,047.0
Operating income	47.2	79.0	147.2	26.7
Other (expense) income:
Interest income	0.2	1.1	1.2	1.7
Interest expense	(30.1)	(39.0)	(59.2)	(73.8)
Loss on sale of business	0.0	0.0	(8.6)	0.0
Loss on extinguishment of debt	0.0	0.0	(1.8)	(0.7)
Other expense, net	(3.9)	(5.6)	(9.8)	(11.7)
Total other expense	(33.8)	(43.5)	(78.2)	(84.5)
Income (loss) before income taxes	13.4	35.5	69.0	(57.8)
Income tax expense (benefit)	11.6	18.5	11.3	(4.8)
Net income (loss) from continuing operations	1.8	17.0	57.7	(53.0)
Net (loss) income from discontinued operations	0.0	(0.7)	0.0	5.4
Net income (loss)	$ 1.8	$ 16.3	$ 57.7	$ (47.6)
Income (loss) per common share:
Basic from continuing operations (in dollars per share)	$ 0.01	$ 0.10	$ 0.34	$ (0.33)
Basic from discontinued operations (in dollars per share)	0	0	0	0.03
Basic income (loss) per common share (in dollars per share)	0.01	0.10	0.34	(0.30)
Diluted from continuing operations (in dollars per share)	0.01	0.10	0.34	(0.33)
Diluted from discontinued operations (in dollars per share)	0	0	0	0.03
Diluted income (loss) per common share (in dollars per share)	$ 0.01	$ 0.10	$ 0.34	$ (0.30)
Weighted average common shares outstanding:
Basic (in shares)	168.9	169.8	168.8	159.5
Diluted (in shares)	169.6	170.7	169.6	159.5