Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net income (loss)	$ 30,086	$ (13,878)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion and amortization	35,013	38,059
Accretion of asset retirement obligation and receivable	7,007	7,031
Share-based compensation	2,578	1,522
Non-cash interest expense	2,269	1,327
Amortization of deferred financing costs	3,214	2,532
Loss (gain) on derivative instruments	2,600	(5,276)
Loss (gain) on foreign exchange	1,387	(2,109)
Income from equity affiliates	(1,293)	(2,025)
Deferred income tax expense (benefit)	(47,973)	2,766
Other	299	(499)
Changes in operating assets and liabilities:
Receivables	(10,052)	(15,899)
Inventories	(6,956)	(4,957)
Accounts payable and accrued expenses	2,098	12,336
Deferred revenue	3,389	605
Asset retirement obligation	(7,977)	(4,838)
Other assets and liabilities	2,552	(15,057)
Net cash provided by operating activities	18,241	1,640
Cash flows from investing activities:
Additions to property, plant and equipment	(5,548)	(13,027)
Change in restricted investments	(3,172)	2,106
Cash payments in escrow for future acquisitions	0	34,000
Cash payments related to acquisitions and other	(126,865)	(35,887)
Cash acquired related to acquisition, net	0	2,783
Proceeds from sale of restricted investments	1,626	1,123
Payments related to loan and lease receivables	1,620	2,591
Payments related to loan and lease receivables	(312)	(1,044)
Other	1,530	(3,295)
Net cash used in investing activities	(131,121)	(10,650)
Cash flows from financing activities:
Borrowings from long-term debt, net of debt discount	121,225	79,359
Repayments of long-term debt	(9,018)	(17,160)
Borrowings on revolving lines of credit	77,500	32,675
Repayments of revolving lines of credit	(79,500)	(42,251)
Debt issuance costs and other refinancing costs	(2,927)	(2,806)
Other	(262)	98
Net cash provided by financing activities	107,018	49,915
Effect of exchange rate changes on cash	680	(1,770)
Net increase (decrease) in cash and cash equivalents	(5,182)	39,135
Cash and cash equivalents, beginning of period	22,936	14,258
Cash and cash equivalents, end of period	17,754	53,393
Non-cash transactions:
Accrued purchases of property and equipment	2,279	8,107
Capital leases and other financing sources	$ 0	$ 12,700