Net revenues (Details) - Sales Revenue, Net - Customer Concentration Risk	3 Months Ended
Mar. 31, 2019
Hospitals And Healthcare Providers
Concentration Risk [Line Items]
Percentage of total revenue	87.00%
Other Medical Device Manufacturers
Concentration Risk [Line Items]
Percentage of total revenue	10.00%
Home Care Providers
Concentration Risk [Line Items]
Percentage of total revenue	3.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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