Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities:
Net income	$ 277,911	$ 240,388
Income (loss) from discontinued operations, net of tax	(484)	26
Income from continuing operations	278,395	240,362
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	212,832	187,937
Deferred income taxes	16,409	49,222
Changes in current assets and liabilities, net of acquisitions:
Receivables	(100,141)	(238,373)
Inventories	(9,581)	2,480
Other current assets	1,269	(69,105)
Accounts payable	19,125	13,062
Other current liabilities	74,286	53,458
Other noncurrent changes	(10,139)	(35,361)
Net cash provided by continuing operations	482,455	203,682
Net cash used in discontinued operations	(688)	(579)
Net cash provided by operating activities	481,767	203,103
Investing activities:
Capital expenditures	(413,842)	(423,036)
Acquisitions, net of cash acquired	(71,479)	(53,263)
Net proceeds from sale or disposition of property and other	23,463	28,391
Investments	24	(717)
Net cash used in investing activities	(461,834)	(448,625)
Financing activities:
Issuance of short-term borrowings	75,000	169,977
Repayment of short-term borrowings	0	(30,000)
Issuance of long-term debt	100,125	302,724
Repayment of long-term debt	(73,699)	(166,956)
Proceeds from issuance of common stock	3,410	105,639
Dividends paid	(124,796)	(119,795)
Tax withholding on stock-based compensation	(362)	(3,015)
Net cash provided by (used in) financing activities	(20,322)	258,574
Increase (decrease) in cash and cash equivalents	(389)	13,052
Cash and cash equivalents -- beginning of year	66,459	53,948
Cash and cash equivalents -- end of period	$ 66,070	$ 67,000