Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net income (loss)	$ 13,773	$ (23,641)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation	9,319	9,541
Amortization	2,853	2,843
Provision for doubtful accounts	(1,661)	0
Deferred income taxes	685	39,000
Gain (loss) on the sale of property, plant and equipment	2	(46)
Stock-based compensation expense	2,772	2,870
Leases	543	0
Changes in operating assets and liabilities, net of effects from business acquisition:
Accounts receivable	64,176	33,419
Contract assets	(16,943)	(1,127)
Inventories	(5,862)	(38,210)
Prepaid expenses and other assets	3,056	5,944
Accounts payable	(45,914)	2,337
Accrued liabilities	(11,044)	(9,116)
Income taxes	659	716
Net cash provided by operations	16,414	24,530
Cash flows from investing activities:
Additions to property, plant and equipment	(9,326)	(20,059)
Proceeds from the sale of property, plant and equipment	1	57
Additions to purchased software	(748)	(818)
Other	(98)	(179)
Net cash used in investing activities	(10,171)	(20,999)
Cash flows from financing activities:
Proceeds from stock options exercised	279	3,079
Employee taxes paid for shares withheld	(1,236)	(763)
Dividends paid	(6,203)	0
Borrowings under credit agreement	0	50,000
Principal payments on long-term debt	(274)	(54,551)
Share repurchases	(61,080)	(58,381)
Equity forward contract related to accelerated share repurchase	0	(10,000)
Net used in financing activities	(68,514)	(70,616)
Effect of exchange rate changes	(515)	866
Net decrease in cash and cash equivalents	(62,786)	(66,219)
Cash and cash equivalents at beginning of year	458,102	742,546
Cash and cash equivalents at end of period	$ 395,316	$ 676,327