CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
OPERATING ACTIVITIES
Net income	$ 221,800	$ 91,271
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and other non-cash charges	130,834	98,678
Stock-based compensation expense	5,423	3,862
Loss (gain) on disposition of assets, net	2,690	(1,574)
Deferred income tax provision (benefit)	57,587	(5,447)
Excess tax benefits for share-based payments	(3,434)	(642)
Changes in current assets and liabilities:
Accounts receivable	(143,422)	(149,313)
Income taxes receivable	18,311	18,038
Inventories	(29,319)	(6,057)
Prepaid expenses and other current assets	(11,344)	1,875
Accounts payable	54,500	12,600
Income taxes payable	(1,803)	13,147
Accrued payroll and related expenses	4,197	11,803
Accrued insurance expenses	900	838
Accrued state, local and other taxes	3,151	2,940
Other accrued expenses	1,008	(47)
Changes in working capital	(103,821)	(94,176)
Changes in other assets and liabilities:
Pension liabilities	382	604
Accrued insurance expenses	400	(73)
Other non-current assets	576	(604)
Other non-current liabilities	478	731
Net cash provided by operating activities	312,915	92,630
INVESTING ACTIVITIES
Capital expenditures	(305,729)	(106,106)
Proceeds from sale of assets	18,897	10,751
Net cash used for investing activities	(286,832)	(95,355)
FINANCING ACTIVITIES
Payment of dividends	(32,501)	(13,766)
Borrowings from notes payable to banks	610,450	382,200
Repayments of notes payable to banks	(590,900)	(364,200)
Debt issue costs for notes payable to banks	(415)	(1,886)
Excess tax benefits for share-based payments	3,434	642
Cash paid for common stock purchased and retired	(18,857)	(1,647)
Proceeds received upon exercise of stock options	641	127
Net cash (used for) provided by financing activities	(28,148)	1,470
Net decrease in cash and cash equivalents	(2,065)	(1,255)
Cash and cash equivalents at beginning of period	9,035	4,489
Cash and cash equivalents at end of period	6,970	3,234
Supplemental Information:
Interest paid	3,115	1,670
Income taxes paid, net	61,172	31,824
Change in accounts payable for capital expenditures	$ 6,624	$ 15,810