Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Operating activities:
Net income (loss)	$ 89,904	$ 88,044
Income (loss) from discontinued operations, net of tax	5,006	280
Income (loss) from continuing operations	84,898	87,764
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	169,007	167,964
Earnings, net of distributions, from equity method investments	1,251	512
Deferred income taxes	76,987	60,960
Changes in current assets and liabilities, net of acquisitions:
Receivables	(2,470)	17,259
Inventories	(58,367)	(29,154)
Other current assets	(33,556)	(19,600)
Accounts payable	(7,119)	(3,197)
Other current liabilities	(45,562)	(9,753)
Other noncurrent changes	(10,070)	(17,969)
Net cash provided by continuing operations	174,999	254,786
Net cash used in discontinued operations	(258)	(491)
Net cash provided by operating activities	174,741	254,295
Investing activities:
Capital expenditures	(388,449)	(224,934)
Acquisitions, net of cash acquired	(65,767)	(157)
Net proceeds from sale or disposition of property and other	29,454	16,145
Investments	11,172	(9,955)
Net cash used in continuing operations	(413,590)	(218,901)
Net cash provided by discontinued operations	0	0
Net cash used in investing activities	(413,590)	(218,901)
Financing activities:
Repayment of short-term borrowings	0	(20,000)
Issuance of long-term debt	299,945	6,000
Repayment of long-term debt	(58,605)	(81,202)
Proceeds from issuance of common stock	88	5,744
Dividends paid	(63,594)	(61,623)
Excess tax benefit on stock-based compensation	26	1,248
Net cash provided by (used in) continuing operations	177,860	(149,833)
Net cash provided by discontinued operations	0	0
Net cash provided by (used in) financing activities	177,860	(149,833)
Effect of exchange rate changes on cash and cash equivalents	(140)	133
Decrease in cash and cash equivalents	(61,129)	(114,306)
Cash and cash equivalents - beginning of year	162,772	222,074
Cash and cash equivalents - end of year	$ 101,643	$ 107,768