Product Sales - Schedule of Concentration of Risk, by Risk Factor (Details) - Gross Sales Revenue - Customer concentration risk	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Besse Medical, a subsidiary of AmerisourceBergen Corporation
Concentration Risk [Line Items]
Concentration risk, percentage	56.00%	56.00%	57.00%	55.00%
McKesson Corporation
Concentration Risk [Line Items]
Concentration risk, percentage	34.00%	35.00%	32.00%	37.00%

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.

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