Consolidated Statements of Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Net Sales		$ 4,489,927	$ 4,448,875	$ 4,089,854
Cost of Goods Sold	[1]	3,776,183	3,759,112	3,455,306
Gross profit		713,744	689,763	634,548
Selling, general and administrative expenses	[1]	315,703	308,376	305,173
Rationalization charges		56,351	6,253	5,826
Other pension and postretirement income	[1]	(17,796)	(36,966)	(33,441)
Income Before Interest and Income Taxes		359,486	412,100	356,990
Interest and other debt expense before loss on early extinguishment of debt		105,674	116,306	110,257
Loss on early extinguishment of debt		1,676	2,493	7,052
Interest and other debt expense		107,350	118,799	117,309
Income before income taxes		252,136	293,301	239,681
Provision (benefit) for income taxes		58,322	69,307	(29,978)
Net income		$ 193,814	$ 223,994	$ 269,659
Basic net income per share (in dollars per share)		$ 1.75	$ 2.03	$ 2.44
Diluted net income per share (in dollars per share)		$ 1.74	$ 2.01	$ 2.42

[1] Cost of goods sold, selling, general and administrative expenses and other pension and postretirement income include the impact of the Accounting Standards Update issued by the Financial Accounting Standards Board which amended the presentation of net periodic pension and postretirement benefit costs to report certain components, including interest cost, expected return on the plan assets, amortization of prior service cost or credits and actuarial gains and losses, separately. For 2017 these items have been reclassified from cost of goods sold and selling, general and administrative expenses to other pension and postretirement income.