CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Activities
Net earnings	$ 515,805	$ 601,185	$ 419,491
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation, depletion, accretion and amortization	346,246	305,965	284,940
Net gain on sale of property, plant & equipment and businesses	(14,944)	(17,827)	(15,431)
Contributions to pension plans	(109,631)	(20,023)	(9,576)
Share-based compensation expense	25,215	26,635	20,670
Deferred tax expense (benefit)	64,639	(235,697)	33,591
Cost of debt purchase	6,922	140,772	0
(Increase) decrease in assets excluding the initial effects of business acquisitions and dispositions
Accounts and notes receivable	63,230	(81,561)	(72,763)
Inventories	(34,976)	(14,121)	1,625
Prepaid expenses	(2,167)	(28,445)	2,558
Other assets	(58,489)	(23,759)	(18,236)
Increase (decrease) in liabilities excluding the initial effects of business acquisitions and dispositions
Accrued interest and income taxes	12,148	1,303	(7,187)
Trade payables and other accruals	40,181	9,823	30,353
Other noncurrent liabilities	(26,901)	(32,592)	(29,138)
Other, net	5,499	13,020	3,691
Net cash provided by operating activities	832,777	644,678	644,588
Investing Activities
Purchases of property, plant & equipment	(469,088)	(459,566)	(350,148)
Proceeds from sale of property, plant & equipment	22,210	15,756	23,318
Proceeds from sale of businesses	11,256	287,292	0
Payment for businesses acquired, net of acquired cash	(221,419)	(1,109,725)	(32,537)
Other, net	(12,850)	(3,248)	2,173
Net cash used for investing activities	(669,891)	(1,269,491)	(357,194)
Financing Activities
Proceeds from short-term debt	739,900	5,000	3,000
Payment of short-term debt	(606,900)	(5,000)	(3,000)
Payment of current maturities and long-term debt	(892,055)	(1,463,308)	(130)
Proceeds from issuance of long-term debt	850,000	2,200,000	0
Debt issuance and exchange costs	(45,513)	(15,291)	(1,860)
Settlements of interest rate derivatives	3,378	0	0
Purchases of common stock	(133,983)	(60,303)	(161,463)
Dividends paid	(148,109)	(132,335)	(106,333)
Share-based compensation, shares withheld for taxes	(31,846)	(25,323)	(34,799)
Net cash provided by (used for) financing activities	(265,128)	503,440	(304,585)
Net decrease in cash and cash equivalents and restricted cash	(102,242)	(121,373)	(17,191)
Cash and cash equivalents and restricted cash at beginning of year	146,646	268,019	285,210
Cash and cash equivalents and restricted cash at end of year	$ 44,404	$ 146,646	$ 268,019