Industry and Geographic Information Industry and Geographic Information - Revenue by Category (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenues	$ 126,492	$ 117,399	$ 382,712	$ 389,697
Rapid Immunoassay
Disaggregation of Revenue [Line Items]
Total revenues	42,534	35,366	126,800	132,740
Cardiac Immunoassay
Disaggregation of Revenue [Line Items]
Total revenues	66,820	65,287	200,674	203,581
Specialized Diagnostic Solutions
Disaggregation of Revenue [Line Items]
Total revenues	12,455	12,294	40,595	39,859
Molecular Diagnostic Solutions
Disaggregation of Revenue [Line Items]
Total revenues	$ 4,683	$ 4,452	$ 14,643	$ 13,517