CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Operating Activities
Net earnings	$ 355,958	$ 270,174
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation, depletion, accretion and amortization	203,475	194,951
Noncash operating lease expense	20,867	17,977
Net gain on sale of property, plant & equipment and businesses	(117,376)	(741)
Contributions to pension plans	(4,097)	(4,409)
Share-based compensation expense	17,688	15,220
Deferred tax expense	41,103	36,644
Changes in assets and liabilities before initial effects of business acquisitions and dispositions	(135,007)	(101,271)
Other, net	15,262	(2,954)
Net cash provided by operating activities	397,873	425,591
Investing Activities
Purchases of property, plant & equipment	(192,234)	(223,147)
Proceeds from sale of property, plant & equipment	190,747	3,063
Proceeds from sale of businesses	0	651
Payment for businesses acquired, net of acquired cash	0	5,668
Other, net	15	5,575
Net cash used for investing activities	(1,472)	(219,526)
Financing Activities
Payment of current maturities and long-term debt	(500,013)	(250,012)
Proceeds from issuance of long-term debt	0	750,000
Debt issuance and exchange costs	(13,286)	(10,762)
Settlements of interest rate derivatives	0	(19,863)
Purchases of common stock	0	(26,132)
Dividends paid	(98,173)	(90,128)
Share-based compensation, shares withheld for taxes	(12,782)	(15,830)
Other, net	(1,754)	(645)
Net cash provided by (used for) financing activities	(626,008)	336,628
Net increase (decrease) in cash and cash equivalents and restricted cash	(229,607)	542,693
Cash and cash equivalents and restricted cash at beginning of year	1,198,013	274,506
Cash and cash equivalents and restricted cash at end of period	$ 968,406	$ 817,199