Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	$ (227,626)	$ 160,290
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	1,589,753	1,291,242
Net income	1,720	34,579
Net Income (Loss) Attributable to Parent	1,921	34,543
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	30,816	26,640
Share-based compensation	6,338	4,490
Unrealized foreign exchange loss (gain), net	18,806	(3,208)
Deferred income taxes	(2,043)	3,468
Accretion of convertible debt discount and amortization of debt issuance costs	4,616	4,071
Changes in working capital, net of amounts acquired:
Income taxes payable, net	(10,454)	635
Trade accounts receivable	300,063	(31,456)
Prepaid expenses and other current assets	(119,648)	33,787
Trade accounts payable	(126,242)	(115,380)
Accrued expenses and other current liabilities	14,811	51,377
Deferred revenue	4,119	3,005
Changes in noncurrent assets and liabilities	(17,018)	953
Net cash provided by operating activities	105,884	12,961
Cash flows from investing activities:
Acquisitions, net of cash acquired	475	0
Purchases of property and equipment	(30,392)	(31,390)
Purchases of other long-term assets	(2,046)	(1,783)
Other, net	357	187
Net cash used in investing activities	(31,606)	(32,986)
Cash flows from financing activities:
Proceeds from issuance of shares	1,700	5,171
Repurchase of shares	(240,530)	(2,275)
Borrowings from revolving credit agreements	805,500	1,209,446
Repayments of revolving credit agreements	(805,500)	(1,425,398)
Proceeds from Convertible Debt	0	525,000
Repayments of long-term debt obligations	0	(94,199)
Borrowings from short-term debt obligations, net	(2,163)	(11,779)
Payments of Debt Issuance Costs	0	(11,812)
Other, net	(1,651)	(1,452)
Net cash provided by financing activities	(242,644)	192,702
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	(59,260)	(12,387)
Interest paid during the period	3,678	5,491
Income taxes paid during the period	$ 16,064	$ 12,074