Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 70,791	$ 66,767
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	55,337	54,868
Share-based compensation expense	20,433	15,426
Amortization of debt issuance costs	2,017	1,448
Asset disposal and exit costs	0	(703)
(Gain) loss on fixed asset disposal	(2,010)	1,189
Deferred income taxes	16,439	(6,463)
Mark-to-market on derivative instruments	(262)	4,356
Noncash patronage dividends received	(1,270)	(410)
Loss in equity method investments	6,497	542
Other	(492)	130
Net change in operating assets and liabilities, net of acquisition/divestitures	(60,617)	(19,401)
Net cash provided by operating activities	106,863	117,749
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in equity method investments	(701)	(47,285)
Payments for acquisitions, net of cash acquired of $1,530 and $5,638	(38,672)	(603,373)
Proceeds from acquisition adjustments	346	0
Payments for property, plant, and equipment	(140,637)	(139,850)
Proceeds from sale of fixed assets	8,880	122
Net cash used in investing activities	(170,784)	(790,386)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from the issuance of debt	0	500,000
Repayment of debt	(10,000)	(10,000)
Payments on capital lease obligations	(584)	(508)
Proceeds from revolver line of credit	270,345	489,850
Payments on revolver line of credit	(222,100)	(340,060)
Proceeds from exercise of stock options	3,558	1,281
Minimum tax withholding paid on behalf of employees for restricted stock units	(7,565)	(3,491)
Excess tax benefit from share-based compensation	11,345	3,196
Payment of deferred financing costs	(39)	(3,378)
Net cash provided by financing activities	44,960	636,890
Effect of exchange rate changes on cash and cash equivalents	(3,871)	595
DECREASE IN CASH AND CASH EQUIVALENTS	(22,832)	(35,152)
Cash and cash equivalents, beginning of period	50,240	101,105
Cash and cash equivalents, end of period	27,408	65,953
SUPPLEMENTAL CASH FLOW INFORMATION
Non-cash activity - Unpaid purchases of plant and equipment	21,673	32,854
Non-cash activity - Conversion of phantom shares to restricted stock units	$ 0	$ 956