CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
ASSETS
Cash and cash equivalents	$ 5,734	$ 7,393
Accounts receivable, net	425,766	461,272
Inventories	111,813	100,438
Deferred income taxes	10,035	7,183
Income taxes receivable	561	10,805
Prepaid expenses	7,325	8,478
Other current assets	30,393	30,986
Total current assets	591,627	626,555
Property, plant and equipment, net	736,888	675,360
Goodwill	24,093	24,093
Other assets	16,399	12,203
Total assets	1,369,007	1,338,211
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable	132,383	122,987
Accrued payroll and related expenses	26,751	33,680
Accrued insurance expenses	6,138	5,744
Accrued state, local and other taxes	5,701	5,066
Income taxes payable	35,403	10,705
Other accrued expenses	384	1,284
Total current liabilities	206,760	179,466
Long-term accrued insurance expenses	9,254	9,000
Notes payable to banks	180,800	203,300
Long-term pension liabilities	22,418	24,445
Other long-term liabilities	1,938	3,480
Deferred income taxes	147,439	155,928
Total liabilities	568,609	575,619
Common stock	21,949	22,119
Retained earnings	790,893	753,119
Accumulated other comprehensive loss	(12,444)	(12,646)
Total stockholders' equity	800,398	762,592
Total liabilities and stockholders' equity	$ 1,369,007	$ 1,338,211