CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales	$ 7,795,025	$ 7,710,226	$ 8,121,661
Cost of sales	5,977,348	5,722,710	6,147,252
Gross profit	1,817,677	1,987,516	1,974,409
Operating costs and expenses:
Selling and distribution	1,346,948	1,348,349	1,379,317
General and administrative	311,176	346,028	350,324
Amortization of intangibles	20,710	20,752	21,653
Facility closing and reorganization costs, net	24,913	8,719	19,844
Impairment of intangible and long-lived assets	30,668	0	109,910
Total operating costs and expenses	1,734,415	1,723,848	1,881,048
Operating income	83,262	263,668	93,361
Other (income) expense:
Interest expense	64,961	66,795	66,813
Loss on early retirement of long-term debt	0	0	43,609
Other income, net	(2,942)	(5,778)	(3,751)
Total other expense	62,019	61,017	106,671
Income (loss) from continuing operations before income taxes	21,243	202,651	(13,310)
Income tax expense (benefit)	(26,179)	82,034	(5,229)
Income (loss) from continuing operations	47,422	120,617	(8,081)
Income (loss) from discontinued operations, net of tax	11,291	(312)	(1,095)
Gain (loss) on sale of discontinued operations, net of tax	2,875	(376)	668
Net income (loss)	$ 61,588	$ 119,929	$ (8,508)
Average common shares:
Basic (shares)	90,899,284	90,933,886	93,298,467
Diluted (shares)	91,273,994	91,510,483	93,298,467
Basic income (loss) per common share:
Income (loss) from continuing operations (USD per share)	$ 0.52	$ 1.33	$ (0.09)
Income (loss) from discontinued operations (USD per share)	0.16	(0.01)	0.00
Net income (loss) (USD per share)	0.68	1.32	(0.09)
Diluted income (loss) per common share:
Income (loss) from continuing operations (USD per share)	0.52	1.32	(0.09)
Income (loss) from discontinued operations (USD per share)	0.15	(0.01)	0.00
Net income (loss) (USD per share)	$ 0.67	$ 1.31	$ (0.09)