Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash Flows from Operating Activities:
Net income (loss)	$ (85,532)	$ (148,188)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	153,357	164,674
Deferred income tax provision (benefit)	(8,171)	27,021
Net loss (gain) on sales of property and equipment and cost method investment	(4,935)	(8,513)
Noncash compensation	8,202	8,562
Excluding the effects of acquisitions, increase (decrease) in cash from:
Accounts receivable and contract assets	51,629	(85,278)
Inventory	(10,765)	(7,094)
Other operating assets	16,502	6,377
Currency translation effect on working capital, excluding cash	(4,375)	2,495
Current liabilities	(340)	60,998
Other operating liabilities	(3,405)	14,602
Total adjustments to net income (loss)	197,699	183,844
Net Cash Provided by (Used in) Operating Activities	112,167	35,656
Cash Flows from Investing Activities:
Purchases of property and equipment	(128,847)	(83,919)
Business acquisitions, net of cash acquired	0	(68,398)
Proceeds from Sale and Maturity of Debt Securities, Available-for-sale	0	62,021
Purchase of Angolan bonds	0	(10,417)
Distributions of capital from unconsolidated affiliates	2,395	2,372
Proceeds from Sale and Maturity of Other Investments		15,897
Dispositions of property and equipment	6,406
Net Cash Provided by (Used in) Investing Activities	(120,046)	(82,444)
Cash Flows from Financing Activities:
Net proceeds from issuance of 6.000% Senior Notes, net of issuance costs	0	295,816
Repayment of term loan facility	0	(300,000)
Other financing activities	(2,320)	(1,565)
Net Cash Provided by (Used in) Financing Activities	(2,320)	(5,749)
Effect of exchange rates on cash	(3,737)	(10,629)
Net Increase (Decrease) in Cash and Cash Equivalents	(13,936)	(63,166)
Cash and Cash Equivalents—Beginning of Period	354,259	$ 430,316
Cash and Cash Equivalents—End of Period	$ 340,323