CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 86,098	$ 94,250
Trade accounts and other receivables, net	107,036	125,179
Inventories:
Finished goods	98,175	87,218
Raw materials and supplies	41,813	47,042
Total inventories	139,988	134,260
Prepaid expenses and other current assets	4,706	5,442
Prepaid income taxes		1,888
Deferred income taxes	10,483	10,363
Total current assets	348,311	371,382
Property, plant and equipment:
Land and land improvements	31,225	31,163
Land-use and mineral rights	14,138	12,751
Buildings	72,425	72,702
Machinery and equipment	532,402	535,529
Construction in progress	145,191	109,735
Total	795,381	761,880
Less accumulated depreciation and amortization	291,762	283,345
Net property, plant and equipment	503,619	478,535
Goodwill	12,164	12,164
Intangible and other assets, net	18,633	16,870
Total assets	882,727	878,951
Current liabilities:
Accounts payable	23,985	24,570
Accrued payroll and benefits	5,959	13,650
Accrued freight	9,032	6,873
Accrued income taxes	6,367
Dividends payable	6,931
Other accrued expenses	10,939	11,595
Total current liabilities	63,213	56,688
Deferred income taxes	52,901	53,676
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 shares authorized; 23,102,178 and 23,080,632 shares issued and outstanding at March 31, 2014 and December 31, 2013, respectively	231	231
Additional paid-in capital	55,052	56,782
Retained earnings	717,669	714,835
Accumulated other comprehensive loss	(6,339)	(3,261)
Total shareholders' equity	766,613	768,587
Total liabilities and shareholders' equity	$ 882,727	$ 878,951