CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Operating Activities
Net earnings	$ 391,783	$ 273,639
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation, depletion, accretion and amortization	256,463	227,974
Net gain on sale of property, plant & equipment and businesses	(8,374)	(4,630)
Contributions to pension plans	(107,202)	(17,638)
Share-based compensation expense	21,650	19,953
Deferred tax expense (benefit)	76,779	11,298
Cost of debt purchase	6,922	43,048
Changes in assets and liabilities before initial effects of business acquisitions and dispositions	(67,836)	(162,849)
Other, net	2,446	8,740
Net cash provided by operating activities	572,631	399,535
Investing Activities
Purchases of property, plant & equipment	(348,238)	(366,845)
Proceeds from sale of property, plant & equipment	12,838	10,403
Proceeds from sale of businesses	11,256	0
Payment for businesses acquired, net of acquired cash	(213,138)	(210,562)
Other, net	(12,216)	405
Net cash used for investing activities	(549,498)	(566,599)
Financing Activities
Proceeds from short-term debt	514,900	5,000
Payment of short-term debt	(314,900)	(5,000)
Payment of current maturities and long-term debt	(892,049)	(800,572)
Proceeds from issuance of long-term debt	850,000	1,600,000
Debt issuance and exchange costs	(45,513)	(15,046)
Settlements of interest rate derivatives	3,378	0
Purchases of common stock	(99,916)	(60,303)
Dividends paid	(111,192)	(99,263)
Share-based compensation, shares withheld for taxes	(31,418)	(24,608)
Net cash provided by (used for) financing activities	(126,710)	600,208
Net increase (decrease) in cash and cash equivalents and restricted cash	(103,577)	433,144
Cash and cash equivalents and restricted cash at beginning of year	146,646	268,019
Cash and cash equivalents and restricted cash at end of period	$ 43,069	$ 701,163