Balance Sheet Account Details - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 170,347	$ 144,260
Less: accumulated depreciation and amortization	96,446	82,675
Property, Plant and Equipment, Net	73,901	61,585
Depreciation and amortization	17,700	14,600	$ 13,400
Equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	89,285	75,728
Building and improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	37,335	34,994
Leased instruments
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	42,647	32,458
Land
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 1,080	$ 1,080