New Accounting Pronouncements (Condensed Consolidated Cash Flow) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income (loss)	$ (23,641)	$ 8,555
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation	9,541	9,320
Amortization	2,843	2,953
Deferred income taxes	39,000	74
Gain on the sale of property, plant and equipment	(46)	(197)
Stock-based compensation expense	2,870	2,160
Changes in operating assets and liabilities:
Accounts receivable	33,419	59,685
Contract assets	(1,127)	6,561
Inventories	(38,210)	(29,582)
Prepaid expenses and other assets	5,944	(3,292)
Accounts payable	2,337	16,225
Accrued liabilities	(9,116)	5,256
Income taxes	716	187
Net cash provided by operations	24,530	77,905
Cash flows from investing activities:
Net cash used in investing activities	(20,999)	(7,469)
Cash flows from financing activities:
Net provided by financing activities	(70,616)	267
Effect of exchange rate changes	866	341
Net increase in cash and cash equivalents	(66,219)	71,044
Cash and cash equivalents at beginning of year	742,546	681,433
Cash and cash equivalents at end of period	676,327	752,477
Accounting Standards Update 2014-09 [Member] | As Previously Reported [Member] | Calculated Under Revenue Guidance In Effect Before Topic 606 [Member]
Cash flows from operating activities:
Net income (loss)		9,687
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation		9,320
Amortization		2,953
Deferred income taxes		1,041
Gain on the sale of property, plant and equipment		(197)
Stock-based compensation expense		2,160
Changes in operating assets and liabilities:
Accounts receivable		59,685
Contract assets		0
Inventories		(22,512)
Prepaid expenses and other assets		(5,329)
Accounts payable		16,225
Accrued liabilities		5,256
Income taxes		(384)
Net cash provided by operations		77,905
Cash flows from investing activities:
Net cash used in investing activities		(7,469)
Cash flows from financing activities:
Net provided by financing activities		267
Effect of exchange rate changes		341
Net increase in cash and cash equivalents		71,044
Cash and cash equivalents at beginning of year	742,546	681,433
Cash and cash equivalents at end of period		752,477
Accounting Standards Update 2014-09 [Member] | Restatement Adjustment [Member] | Adjustments [Member]
Cash flows from operating activities:
Net income (loss)		(1,132)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation		0
Amortization		0
Deferred income taxes		(967)
Gain on the sale of property, plant and equipment		0
Stock-based compensation expense		0
Changes in operating assets and liabilities:
Accounts receivable		0
Contract assets		6,561
Inventories		(7,070)
Prepaid expenses and other assets		2,037
Accounts payable		0
Accrued liabilities		0
Income taxes		571
Net cash provided by operations		0
Cash flows from investing activities:
Net cash used in investing activities		0
Cash flows from financing activities:
Net provided by financing activities		0
Effect of exchange rate changes		0
Net increase in cash and cash equivalents		0
Cash and cash equivalents at beginning of year	$ 0	0
Cash and cash equivalents at end of period		$ 0