CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
Net cash (used in) provided by operating activities	$ (5,304)	$ 31,344
Cash flows from investing activities:
Capital expenditures	(29,457)	(110,346)
Grants received for capital expenditures		236
Proceeds from sale of business	105,067	20,837
Proceeds from sale of assets	1,243	4,777
Net cash provided by (used in) investing activities	76,853	(84,496)
Cash flows from financing activities:
Net (payments) proceeds of commercial paper	(40,700)	6,350
Borrowings under credit agreement	65,000	3,000
Payments under credit agreement	(70,500)	(3,000)
Issuances of notes payable		50,000
Payments under industrial development bond agreement		(19,000)
Proceeds from stock option exercises	406
Dividends paid	(4,446)	(4,438)
Net cash (used in) provided by financing activities	(50,240)	32,912
Net increase (decrease) in cash and cash equivalents	21,309	(20,240)
Cash and cash equivalents, beginning of period	4,044	26,661
Cash and cash equivalents, end of period	$ 25,353	$ 6,421