CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income (loss)	$ (143,662)	$ (148,067)
Adjustments to net income (loss):
Depreciation and amortization	214,008	204,364
Deferred income tax expense (benefit)	14,361	(48,469)
Deferred financing costs amortization	1,967	1,728
Discount amortization on long-term debt	5,335	4,505
Losses (gains) on debt buyback		8,596
Losses (gains) on long-lived assets, net	2,257	2,875
Losses (gains) on investments, net	723
Provisions for bad debt	(3,400)	62
Share-based compensation	8,628	10,280
Foreign currency transaction losses (gains), net	2,522	877
Equity in (earnings) losses of unconsolidated affiliates, net of dividends	(2)	(2)
Other	(372)	(751)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	(34,381)	(19,260)
Inventory	(7,835)	(5,301)
Other current assets	22,600	(10,725)
Other long-term assets	6,011	15,294
Trade accounts payable and accrued liabilities	(143,050)	(38,659)
Income taxes payable	836	17,929
Other long-term liabilities	(28,229)	(53,267)
Net cash (used for) provided by operating activities	(81,683)	(57,991)
Cash flows from investing activities:
Purchases of investments	(676)	(4)
Sales and maturities of investments	1,148	91
Capital expenditures	(94,026)	(183,427)
Proceeds from sales of assets and insurance claims	3,076	3,253
Other	1,034	(106)
Net cash (used for) provided by investing activities	(89,444)	(180,193)
Cash flows from financing activities:
Increase (decrease) in cash overdrafts	(383)	(469)
Proceeds from issuance of long-term debt	800,000	411,200
Debt issuance costs	(12,928)	(10,439)
Proceeds from revolving credit facilities	615,000
Reduction in revolving credit facilities	(680,000)
Proceeds from (payments for) issuance of common shares		8,300
Reduction in long-term debt	(460,837)	(170,491)
Dividends to shareholders	(17,148)	(17,040)
Payment for commercial paper	(40,000)
Cash proceeds from equity component of exchangeable debt		159,952
Payments on term loan		(162,500)
Proceeds from (payments for) short-term borrowings	194	16
Purchase of capped call hedge transactions		(40,250)
Other	(1,862)	(5,341)
Net cash (used for) provided by financing activities	202,036	172,938
Effect of exchange rate changes on cash and cash equivalents	(867)	1,841
Net increase (decrease) in cash and cash equivalents	30,042	(63,405)
Cash and cash equivalents, beginning of period	336,997	264,093
Cash and cash equivalents, end of period	$ 367,039	$ 200,688