UNAUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities:
Net (loss) income	$ (55,705)	$ 68,765
Adjustments to reconcile net (loss) income to net cash from operating activities:
Depreciation and amortization	205,480	196,904
Goodwill impairment charge	123,414	0
Pre-tax, non-cash acquisition accounting inventory adjustments	0	13,559
Allowance for doubtful accounts	6,743	5,281
Amortization of deferred financing costs and debt discount	2,457	2,539
Accretion of environmental liabilities	7,975	8,628
Changes in environmental liability estimates	(2,991)	(2,417)
Deferred income taxes	8,506	272
Stock-based compensation	6,446	6,389
Excess tax benefit of stock-based compensation	(829)	(1,589)
Income tax benefit related to stock option exercises	829	1,579
Other income	(4,136)	(2,030)
Environmental expenditures	(12,130)	(15,928)
Changes in assets and liabilities, net of acquisitions
Accounts receivable and unbilled accounts receivable	(35,708)	(88,000)
Inventories and supplies	(20,675)	1,710
Other current assets	(10,048)	27,483
Accounts payable	(53,352)	37,257
Other current and long-term liabilities	29,763	19,712
Net cash from operating activities	196,039	280,114
Cash flows from investing activities:
Additions to property, plant and equipment	(198,877)	(207,641)
Proceeds from sales of fixed assets	5,913	3,700
Proceeds from sales of marketable securities	12,947	0
Acquisitions, net of cash acquired	(6,150)	(59,458)
Additions to intangible assets, including costs to obtain or renew permits	(5,443)	(4,357)
Other	914	(11)
Net cash used in investing activities	(190,696)	(267,767)
Cash flows from financing activities:
Change in uncashed checks	(591)	9,754
Proceeds from exercise of stock options	0	399
Remittance of shares, net	(2,668)	(599)
Repurchases of common stock	(48,329)	0
Proceeds from employee stock purchase plan	4,364	5,327
Deferred financing costs paid	0	(2,446)
Repayment of long-term obligations	(5,000)	0
Payments on capital leases	(1,682)	(4,096)
Issuance costs related to 2012 issuance of common stock	0	(250)
Excess tax benefit of stock-based compensation	829	1,589
Net cash from financing activities	(53,077)	9,678
Effect of exchange rate change on cash	(4,318)	(3,226)
(Decrease) increase in cash and cash equivalents	(52,052)	18,799
Cash and cash equivalents, beginning of period	310,073	229,836
Cash and cash equivalents, end of period	258,021	248,635
Cash payments for interest and income taxes:
Interest paid	58,446	58,084
Income taxes paid	21,737	8,386
Accrual for repurchased shares	5,464	0
Non-cash investing and financing activities:
Property, plant and equipment accrued	23,976	39,804
Transfer of inventory to property, plant and equipment	$ 0	$ 11,369