CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
OPERATING ACTIVITIES
Net (loss) income	$ (61,680)	$ 167,556
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation, amortization and other non-cash charges	208,420	171,382
Stock-based compensation expense	7,695	7,115
Loss on disposition of assets, net	1,115	11,321
Deferred income tax benefit	(52,038)	(35,508)
Excess tax benefits for share-based payments	(1,410)	(4,378)
(Increase) decrease in assets:
Accounts receivable	348,939	(154,687)
Income taxes receivable	3,447	(983)
Inventories	18,629	(27,746)
Prepaid expenses	3,089	3,494
Other current assets	(4,666)	(180)
Other non-current assets	1,691	(1,701)
Increase (decrease) in liabilities:
Accounts payable	(63,200)	53,170
Income taxes payable	5,017	558
Accrued payroll and related expenses	(28,743)	4,841
Accrued insurance expenses	(902)	(546)
Accrued state, local and other taxes	499	5,607
Other accrued expenses	(249)	38
Pension liabilities	(146)	1,218
Long-term accrued insurance expenses	775	(143)
Other long-term liabilities	3	5,846
Net cash provided by operating activities	386,285	206,274
INVESTING ACTIVITIES
Capital expenditures	(155,202)	(237,473)
Proceeds from sale of assets	7,935	14,980
Net cash used for investing activities	(147,267)	(222,493)
FINANCING ACTIVITIES
Payment of dividends	(33,599)	(68,822)
Borrowings from notes payable to banks	588,400	826,800
Repayments of notes payable to banks	(793,400)	(728,100)
Debt issue costs for notes payable to banks		(667)
Excess tax benefits for share-based payments	1,410	4,378
Cash paid for common stock purchased and retired	(4,093)	(17,548)
Net cash (used for) provided by financing activities	(241,282)	16,041
Net decrease in cash and cash equivalents	(2,264)	(178)
Cash and cash equivalents at beginning of period	9,772	8,700
Cash and cash equivalents at end of period	7,508	8,522
Supplemental cash flows disclosure:
Interest paid, net of amounts capitalized	1,124	836
Income taxes paid, net	8,535	136,647
Supplemental disclosure of noncash investing activities:
Capital expenditures included in accounts payable	$ 5,349	$ 29,495