Certain Balance Sheet Components Certain Balance Sheet Components (Tables)

3 Months Ended

Mar. 31, 2016

Balance Sheet Related Disclosures [Abstract]

Accounts Receivable, Net [Table Text Block]

Accounts receivable, net	March 31, 2016		December 31, 2015
	(in thousands)
Trade receivables (net of allowance of $4,541 and $5,949)	$	321,814	$	298,550
Unbilled receivables	46,618		32,345
Total accounts receivable, net	$	368,432	$	330,895

Allowance for Credit Losses on Financing Receivables [Table Text Block]

Allowance for doubtful accounts activity	Three Months Ended March 31,
	2016			2015
	(in thousands)
Beginning balance	$	5,949		$	6,195
Provision (release) for doubtful accounts, net	(8		)	269
Accounts written-off	(1,478		)	(16		)
Effect of change in exchange rates	78			(509		)
Ending balance	$	4,541		$	5,939

Inventories [Table Text Block]

Inventories	March 31, 2016		December 31, 2015
	(in thousands)
Materials	$	115,331	$	111,191
Work in process	10,836		9,400
Finished goods	62,843		69,874
Total inventories	$	189,010	$	190,465

Property, Plant, and Equipment, Net [Table Text Block]

Property, plant, and equipment, net	March 31, 2016			December 31, 2015
	(in thousands)
Machinery and equipment	$	289,411		$	289,015
Computers and software	104,795			104,310
Buildings, furniture, and improvements	128,437			127,531
Land	20,009			19,882
Construction in progress, including purchased equipment	32,567			32,639
Total cost	575,219			573,377
Accumulated depreciation	(385,215		)	(383,121		)
Property, plant, and equipment, net	$	190,004		$	190,256

Depreciation Expense [Table Text Block]

Depreciation expense	Three Months Ended March 31,
	2016		2015
	(in thousands)
Depreciation expense	$	10,464	$	11,382