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)	$ 30,356	$ (4,899)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation	27,920	29,104
Amortization	8,469	10,539
Provision for doubtful accounts	(1,462)	1,714
Deferred income taxes	206	11,863
Asset impairments	834	96
Gain on the sale of property, plant and equipment	(60)	(215)
Stock-based compensation expense	8,461	8,229
Other, net	(652)	0
Changes in operating assets and liabilities, net of effects from business acquisition:
Accounts receivable	121,171	(21,733)
Contract assets	(20,986)	(9,402)
Inventories	(6,557)	(54,342)
Prepaid expenses and other assets	2,944	2,493
Accounts payable	(122,156)	12,620
Accrued liabilities	16,301	2,170
Income taxes	(8,779)	(5,530)
Net cash provided by (used in) operations	57,314	(17,293)
Cash flows from investing activities:
Proceeds from sales of investments at par	50	522
Additions to property, plant and equipment	(23,746)	(50,437)
Proceeds from the sale of property, plant and equipment	231	237
Additions to purchased software	(2,196)	(2,496)
Business acquisitions, net of cash acquired	0	(2,731)
Other	(29)	(130)
Net cash used in investing activities	(25,690)	(55,035)
Cash flows from financing activities:
Proceeds from stock options exercised	1,350	3,463
Employee taxes paid for shares withheld	(1,318)	(822)
Dividends paid	(17,731)	(14,235)
Borrowings under credit agreement	0	50,000
Principal payments on long-term debt	(4,614)	(107,758)
Share repurchases	(118,350)	(122,053)
Debt issuance costs	0	(2,303)
Net cash used in financing activities	(140,663)	(193,708)
Effect of exchange rate changes	(1,021)	(797)
Net decrease in cash and cash equivalents	(110,060)	(266,833)
Cash and cash equivalents at beginning of year	458,102	742,546
Cash and cash equivalents at end of period	$ 348,042	$ 475,713