Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash Flows from Operating Activities:
Consolidated net earnings	$ 45,055	$ 6,159
Adjustments to reconcile consolidated net earnings to net cash provided by operating activities:
Depreciation, depletion and amortization	68,410	67,268
Stock-based compensation expense	7,228	2,907
Gain on divestitures and sales of assets	(100)	(1,576)
Deferred income taxes	17,988	27,774
Excess tax benefits from stock-based compensation transactions	(1,278)	(109)
Other items, net	(2,036)	1,192
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures:
Accounts receivable, net	(29,695)	40,006
Inventories, net	(13,495)	(19,071)
Accounts payable	9,231	(20,328)
Other assets and liabilities, net	(34,300)	(69,097)
Net Cash Provided by Operating Activities	67,008	35,125
Cash Flows from Investing Activities:
Additions to property, plant and equipment	(94,228)	(56,085)
Acquisitions, net	(123,000)	(10,589)
Cash received in acquisition	3,446
Proceeds from divestitures and sales of assets	3,415	1,475
Repayments from affiliate		1,808
Net Cash Used for Investing Activities	(210,367)	(63,391)
Cash Flows from Financing Activities:
Borrowings of debt	210,000
Repayments of debt	(26,390)	(4,738)
Payments on capital lease obligations	(780)	(795)
Change in bank overdraft	(10,235)	(183)
Dividends paid	(25,847)	(28,354)
Issuances of common stock	4,166	9,942
Repurchases of common stock	(150,000)
Excess tax benefits from stock-based compensation transactions	1,278	109
Net Cash Provided by (Used for) Financing Activities	2,192	(24,019)
Net Decrease in Cash and Cash Equivalents	(141,167)	(52,285)
Cash and Cash Equivalents, beginning of period	168,409	108,651
Cash and Cash Equivalents, end of period	27,242	56,366
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	11,394	11,417
Cash paid for income taxes	$ 10,721	$ 18,678