Industry and Geographic Information Industry and Geographic Information - Revenue by Category (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenues	$ 108,252	$ 103,155	$ 256,220	$ 272,298
Rapid Immunoassay
Disaggregation of Revenue [Line Items]
Total revenues	21,772	16,689	84,266	97,374
Cardiac Immunoassay
Disaggregation of Revenue [Line Items]
Total revenues	67,982	69,850	133,854	138,294
Specialized Diagnostic Solutions
Disaggregation of Revenue [Line Items]
Total revenues	14,286	12,694	28,140	27,565
Molecular Diagnostic Solutions
Disaggregation of Revenue [Line Items]
Total revenues	$ 4,212	$ 3,922	$ 9,960	$ 9,065

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration