Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net income	$ 251,294	$ 215,804	$ 236,822
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	130,257	121,408	139,166
Deferred income taxes	(12,350)	25,034	3,629
Stock-based compensation	13,570	14,919	9,047
Change in LIFO reserve	11,990	(53,108)	(35,205)
Amortization of unrecognized postretirement benefits	43,058	46,170	35,907
Pension settlement charges	12,262
Gain on sale of interest in subsidiary, net of tax	0	0	(55,704)
Changes in operating assets and liabilities of continuing operations, net of effect of sale of interest in subsidiary:
Accounts and notes receivable	(45,674)	(15,155)	(64,636)
Inventories	(77,872)	51,864	(524)
Other current assets	3,831	(931)	(2,162)
Accounts payable	13,128	(42,068)	67,734
Accrued liabilities	(23,489)	21,719	25,943
Other items	(10,210)	(85,342)	(40,933)
Net cash provided by operating activities	309,795	300,314	319,084
Investing activities:
Additions to property, plant and equipment and capitalized software	(175,437)	(182,544)	(145,041)
Acquisition of business, net of cash acquired	(5,928)	0	0
Proceeds from sale of interest in subsidiary, net of cash sold	0	0	170,711
Proceeds from the sale of assets	337	1,651	1,248
Net cash (used in) provided by investing activities	(181,028)	(180,893)	26,918
Financing activities:
Net (payments on) issuances of short-term debt	10,019	(41,303)	55,447
Additions to long-term debt	0	0	15,634
Repayments of long-term debt	(935)	(3,125)	(35,715)
Payment of financing fees	0	(2,586)	0
Repurchase of common stock	(107,999)	(108,821)	(200,000)
Payment of dividends to noncontrolling shareholders	(804)	(917)	(7,813)
Payment of dividends	(22,828)	(23,880)	(25,538)
Issuance of common shares and excess tax benefits on options	4,224	23,965	3,230
Net cash used in financing activities	(118,323)	(156,667)	(194,755)
Effects of exchange rate changes on cash of continuing operations	(11,178)	(9,249)	2,674
Changes in cash and cash equivalents	(734)	(46,495)	153,921
Cash and cash equivalents at beginning of year	505,157	551,652	397,731
Cash and cash equivalents at end of year	$ 504,423	$ 505,157	$ 551,652