Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
OPERATING ACTIVITIES
Net income (loss)	$ 24,697	$ (204,516)	$ 83,072
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	37,509	45,448	43,176
Asset impairments	1,217	255,116	0
Interest accretion of convertible notes discount	12,481	11,535	10,662
Financing costs amortization	1,284	1,290	1,392
Employee share-based compensation expense	10,679	11,325	9,420
Unrealized foreign currency transaction loss (gain)	544	78	(1,606)
Deferred income tax benefit	(2,583)	(24,403)	(248)
Other non-cash operating activities	1,276	737	(170)
Changes in assets and liabilities, net of acquisitions:
Accounts receivable	43,618	7,195	43,079
Inventory	25,679	11,988	(8,150)
Unbilled contract revenues and other assets	20,803	12,250	(51,467)
Accounts payable and other liabilities	(11,078)	(17,316)	11,562
Deferred income taxes	(423)	(51)	(3,690)
Customer advances and billings in excess of contract revenue	5,111	(9,710)	(18,413)
Net Cash Provided By Operating Activities	170,814	100,966	118,619
INVESTING ACTIVITIES
Capital expenditures	(17,785)	(47,039)	(62,135)
Payments for China land use rights	0	(11,043)	0
Government grants	1,055	8,650	0
Proceeds from sale of assets	0	425	1,593
Acquisition of businesses, net of cash acquired	(1,351)	(24,517)	(11,943)
Net Cash Used In Investing Activities	(18,081)	(73,524)	(72,485)
FINANCING ACTIVITIES
Borrowings on revolving credit facilities	3,820	68,827	88,819
Repayments on revolving credit facilities	(6,061)	(67,196)	(87,162)
Borrowings on term loan	13,167	0	0
Repayments on term loan	(2,949)	0	0
Payments on long-term debt	0	0	(68,437)
Payments for debt issuance costs	0	0	(1,321)
Payment of contingent consideration	0	(611)	(741)
Proceeds from exercise of stock options	354	486	763
Excess tax benefit from share-based compensation	104	133	1,957
Common stock repurchases	(704)	(948)	(3,367)
Dividend distribution to noncontrolling interests	0	(120)	(1,206)
Proceeds from (Payments for) Other Financing Activities	0	(156)	0
Net Cash Provided By (Used In) Financing Activities	7,731	415	(70,695)
Effect of exchange rate changes on cash	(2,213)	(7,805)	(9,128)
Net increase (decrease) in cash and cash equivalents	158,251	20,052	(33,689)
Cash and cash equivalents at beginning of period	123,708	103,656	137,345
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 281,959	$ 123,708	$ 103,656