CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating Activities
Net income	$ 212,603	$ 267,076
Adjustments to reconcile net income to cash provided by operations:
Depreciation and amortization	76,970	49,375
Stock-based compensation expense	14,539	14,788
Loss on disposal of property, plant and equipment	1,633	151
Excess income tax benefits from exercise of stock options	0	(446)
Changes in operating assets and liabilities, net of acquisitions
Accounts receivable and unbilled accounts receivable	(60,246)	(38,362)
Inventories	(53,365)	2,301
Accounts payable	(121,389)	(43,777)
Accrued income taxes	(35,942)	5,952
Accrued liabilities and customer deposits	81,270	(8,353)
Other assets and liabilities	(89,562)	(1,812)
Net cash provided by operating activities	26,511	246,893
Investing Activities
Purchase of property, plant and equipment	(60,263)	(31,676)
Proceeds from disposal of property, plant and equipment	1,066	140
Acquisitions of businesses, net of cash acquired	(114,175)	(84,355)
Release of deposit in escrow	23,548	0
Net cash used for investing activities	(149,824)	(115,891)
Financing Activities
Proceeds from debt	883,473	346,000
Payments of debt	(918,919)	(215,850)
Purchase of treasury stock	0	(212,176)
Proceeds from exercise of stock options and other benefit plans	2,888	1,773
Payment of income tax withholding on share-based compensation	(6,798)	(9,006)
Excess income tax benefits from exercise of equity options	0	446
Cash dividends ($0.32 and $0.26 per share for the nine months ended September 30, 2017 and 2016, respectively)	(30,693)	(23,523)
Net cash used for financing activities	(70,049)	(112,336)
Effect of changes in currency exchange rates	22,958	5,525
(Decrease) Increase in cash	(170,404)	24,191
Cash, beginning of period	398,484	226,191
Cash, end of period	$ 228,080	$ 250,382