Certain Balance Sheet Components (Tables)

6 Months Ended

Jun. 30, 2019

Balance Sheet Related Disclosures [Abstract]

Accounts Receivable, Net

Accounts receivable, net
In thousands	June 30, 2019		December 31, 2018
Trade receivables (net of allowance of $4,360 and $6,331)	$	426,936	$	416,503
Unbilled receivables	39,430		20,658
Total accounts receivable, net	$	466,366	$	437,161

Allowance for Credit Losses on Financing Receivables

Allowance for doubtful accounts activity	Three Months Ended June 30,						Six Months Ended June 30,
In thousands	2019			2018			2019			2018
Beginning balance	$	4,046		$	4,774		$	6,331		$	3,957
Provision for doubtful accounts, net	365			334			(1,738		)	1,254
Accounts written-off	(80		)	(247		)	(272		)	(505		)
Effect of change in exchange rates	29			(309		)	39			(154		)
Ending balance	$	4,360		$	4,552		$	4,360		$	4,552

Inventories

Inventories
In thousands	June 30, 2019		December 31, 2018
Materials	$	127,219	$	133,398
Work in process	10,888		9,744
Finished goods	91,803		77,532
Total inventories	$	229,910	$	220,674

Property, Plant, and Equipment, Net

Property, plant, and equipment, net
In thousands	June 30, 2019			December 31, 2018
Machinery and equipment	$	321,155		$	315,974
Computers and software	108,110			104,290
Buildings, furniture, and improvements	148,026			146,071
Land	15,201			14,980
Construction in progress, including purchased equipment	51,100			49,682
Total cost	643,592			630,997
Accumulated depreciation	(415,079		)	(404,446		)
Property, plant, and equipment, net	$	228,513		$	226,551

Depreciation Expense

Depreciation expense	Three Months Ended June 30,				Six Months Ended June 30,
In thousands	2019		2018		2019		2018
Depreciation expense	$	12,594	$	12,908	$	24,978	$	26,240