Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 34,866	$ 41,270
Trade accounts and other receivables, net	117,337	112,014
Inventories:
Finished goods	101,173	105,233
Raw materials and supplies	28,965	26,783
Total inventories	130,138	132,016
Prepaid expenses and other current assets	5,488	4,023
Prepaid income taxes		3,279
Deferred income taxes	9,909	9,963
Total current assets	297,738	302,565
Property, plant and equipment:
Land and land improvements	14,510	14,512
Land-use and mineral rights	7,618	8,610
Buildings	70,798	67,120
Machinery and equipment	493,378	455,563
Construction in progress	55,119	48,778
Total	641,423	594,583
Less accumulated depreciation and amortization	220,673	201,924
Net property, plant and equipment	420,750	392,659
Goodwill	12,164	12,164
Intangible and other assets, net	32,624	33,477
Total assets	763,276	740,865
Current liabilities:
Accounts payable	20,101	38,192
Accrued income taxes	1,233
Other accrued expenses	28,392	40,874
Total current liabilities	49,726	79,066
Deferred income taxes	36,476	31,641
Shareholders' equity:
Preferred stock, par value $0.01 per share, 5,000 shares authorized, none outstanding
Common stock, par value $0.01 per share, 80,000,000 and 40,000,000 shares authorized at June 30, 2012 and December 31, 2011, respectively; 23,084,828 and 23,106,358 shares issued and outstanding at June 30, 2012 and December 31, 2011, respectively	231	231
Additional paid-in capital	55,032	56,539
Retained earnings	626,437	577,253
Accumulated other comprehensive loss	(4,626)	(3,865)
Total shareholders' equity	677,074	630,158
Total liabilities and shareholders' equity	$ 763,276	$ 740,865