Certain Balance Sheet Components (Tables)

9 Months Ended

Sep. 30, 2020

Balance Sheet Related Disclosures [Abstract]

Accounts Receivable, Net

A summary of accounts receivable from contracts with customers is as follows:

Accounts receivable, net
In thousands	September 30, 2020		December 31, 2019
Trade receivables (net of allowance of $1,846 and $3,064)	$	314,183	$	415,887
Unbilled receivables	72,737		57,038
Total accounts receivable, net	$	386,920	$	472,925

Allowance for Credit Losses on Financing Receivables

Allowance for doubtful accounts activity	Three Months Ended September 30,				Nine Months Ended September 30,
In thousands	2020		2019		2020		2019
Beginning balance	$	2,102	$	4,360	$	3,064	$	6,331
Provision for (release of) doubtful accounts, net	(21)		(1)		318		(1,739)
Accounts written-off	(278)		(468)		(1,489)		(740)
Effect of change in exchange rates	43		(105)		(47)		(66)
Ending balance	$	1,846	$	3,786	$	1,846	$	3,786

Inventories

Inventories
In thousands	September 30, 2020		December 31, 2019
Raw materials	$	124,662	$	120,861
Work in process	9,016		11,105
Finished goods	71,500		95,930
Total inventories	$	205,178	$	227,896

Property, Plant, and Equipment, Net

Property, plant, and equipment, net
In thousands	September 30, 2020		December 31, 2019
Machinery and equipment	$	306,367	$	323,003
Computers and software	113,639		109,924
Buildings, furniture, and improvements	151,795		149,471
Land	13,771		14,988
Construction in progress, including purchased equipment	33,661		54,490
Total cost	619,233		651,876
Accumulated depreciation	(413,303)		(418,648)
Property, plant, and equipment, net	$	205,930	$	233,228

Depreciation Expense

Depreciation expense	Three Months Ended September 30,				Nine Months Ended September 30,
In thousands	2020		2019		2020		2019
Depreciation expense	$	12,893	$	12,528	$	38,818	$	37,506