Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Net income	$ 172,236	$ 179,769
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	78,726	69,520
Share-based compensation	12,597	11,817
Unrealized foreign exchange loss (gain), net	21,459	(21,035)
Deferred income taxes	(1,208)	(14,856)
Loss from unconsolidated affiliates	117	0
Accretion of convertible debt discount and amortization of debt issuance costs	10,582	10,068
Non-cash impairment of acquired intangible assets	0	2,286
Changes in working capital, net of amounts acquired:
Income taxes payable, net	10,022	10,924
Trade accounts receivable	(87,237)	(7,861)
Prepaid expenses and other current assets	42,552	77,538
Trade accounts payable	(81,149)	(118,677)
Deferred revenue	2,525	(2,497)
Accrued expenses and other current liabilities	9,877	54,233
Changes in noncurrent assets and liabilities	1,474	6,455
Net cash provided by operating activities	192,573	257,684
Cash flows from investing activities:
Acquisitions, net of cash acquired	(12,854)	0
Purchases of property and equipment	(82,129)	(70,871)
Purchases of other long-term assets	(5,787)	(4,651)
Other, net	1,401	1,499
Net cash used in investing activities	(99,369)	(74,023)
Cash flows from financing activities:
Proceeds from issuance of shares	11,757	8,328
Repurchase of shares	(177,163)	(2,310)
Borrowings from revolving credit agreements	4,267,881	1,839,963
Repayments of revolving credit agreements	(4,003,662)	(1,808,695)
Repayments of long-term debt obligations	(51,199)	(6,563)
Repayments of capital lease obligations	(4,739)	(3,473)
Borrowings from short-term debt obligations, net	204,211	99,081
Other, net	1	284
Net cash provided by financing activities	247,087	126,615
Effect of exchange rate changes on cash and cash equivalents and restricted cash	(38,084)	53,494
Increase in cash and cash equivalents and restricted cash	302,207	363,770
Cash and cash equivalents and restricted cash, period start	900,518	812,088
Cash and cash equivalents and restricted cash, period end	1,202,725	1,175,858
Interest paid during the period	19,243	17,359
Income taxes paid during the period	$ 55,338	$ 34,769