2. Significant Customers (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Company's customers that individually comprised greater than 10% of total gross product sales
Percentage of gross product sales	80.00%	90.00%	84.00%	90.00%
McKesson Corporation
Company's customers that individually comprised greater than 10% of total gross product sales
Percentage of gross product sales	32.00%	34.00%	33.00%	34.00%
Amerisource Bergen Drug Corporation
Company's customers that individually comprised greater than 10% of total gross product sales
Percentage of gross product sales	27.00%	33.00%	27.00%	31.00%
Cardinal Health Inc
Company's customers that individually comprised greater than 10% of total gross product sales
Percentage of gross product sales	21.00%	23.00%	24.00%	25.00%