Supplementary Balance Sheet Information (Tables)

12 Months Ended

Dec. 31, 2019

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Inventories

Inventories

	December 31,
	2019		2018
Raw materials	$	76,268	$	69,008
Work-in-process		15,096		15,982
Finished goods		23,431		17,337
Demo and consigned inventory		1,823		2,437
Total inventories	$	116,618	$	104,764

Property, Plant and Equipment, Net

Property, Plant and Equipment, Net

	December 31,
	2019			2018
Cost:
Land, buildings and improvements	$	67,376		$	56,068
Machinery and equipment		87,471			77,918
Total cost		154,847			133,986
Accumulated depreciation		(77,291	)		(68,522	)
Property, plant and equipment, net	$	77,556		$	65,464

Summary of Depreciation Expense on Property, Plant and Equipment, Including Demo Units and Assets under Finance Leases

The following table summarizes depreciation expense on property, plant and equipment, including demo units and assets under finance leases (in thousands):

	Year Ended December 31,
	2019		2018		2017
Depreciation expense	$	11,835	$	11,442	$	9,838

Accrued Expenses and Other Current Liabilities

The following table summarizes accrued expenses and other current liabilities as of the dates indicated (in thousands):

	December 31,
	2019		2018
Accrued compensation and benefits	$	15,359	$	24,545
Accrued warranty		5,756		4,510
Contract liabilities, current portion		3,219		4,165
Deferred purchase price for acquisitions		27,735		—
Other		18,257		13,075
Total	$	70,326	$	46,295

Accrued Warranty

The following table summarizes changes in accrued warranty for the periods indicated (in thousands):

	Year Ended December 31,
	2019			2018			2017
Balance at beginning of year	$	4,510		$	4,835		$	3,142
Provision charged to cost of revenue		2,360			3,111			3,169
Warranty liabilities acquired from acquisitions		142			—			1,307
Use of provision		(1,282	)		(3,341	)		(2,857	)
Foreign currency exchange rate changes		26			(95	)		74
Balance at end of year	$	5,756		$	4,510		$	4,835

Other Long Term Liabilities

The following table summarizes other long term liabilities as of the dates indicated (in thousands):

	December 31,
	2019		2018
Finance lease obligations	$	14,845	$	7,275
Accrued pension liabilities		1,473		3,758
Accrued contingent considerations		16,504		3,376
Other		4,065		2,778
Total	$	36,887	$	17,187