Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net income	$ 40,926	$ 42,437
Operating activities:
Income (loss) from discontinued operations, net of tax	(163)	477
Income from continuing operations	41,089	41,960
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	59,897	52,729
Deferred income taxes	12,658	(2,068)
Changes in current assets and liabilities, net of acquisitions:
Receivables	(2,641)	62,711
Inventories	(21,407)	(29,997)
Other current assets	(31,586)	22,506
Accounts payable	356	(31,864)
Other current liabilities	(6,310)	(5,115)
Other noncurrent changes	(49,965)	(5,302)
Net cash provided by continuing operations	2,091	105,560
Net cash provided by (used in) discontinued operations	(507)	231
Net cash provided by operating activities	1,584	105,791
Investing activities:
Capital expenditures	(133,839)	(105,136)
Acquisitions, net of cash acquired	(30,868)	0
Net proceeds from sale or disposition of property and other	4,938	5,966
Investments	(340)	(1,074)
Net cash used in investing activities	(160,109)	(100,244)
Financing activities:
Issuance of short-term borrowings	70,000	0
Issuance of long-term debt	141,338	101,588
Repayment of long-term debt	(52,964)	(37,047)
Proceeds from issuance of common stock	38,634	0
Dividends paid	(39,695)	(38,573)
Repurchase of common stock	0	(5,020)
Tax withholding on stock-based compensation	(3,015)	(2,330)
Net cash provided by financing activities	154,298	18,618
Increase (decrease) in cash and cash equivalents	(4,227)	24,165
Cash and cash equivalents -- beginning of year	53,948	34,599
Cash and cash equivalents -- end of period	$ 49,721	$ 58,764