Revenues (Details Textual)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Revenues In Percentage From Anti-CD20 Therapeutic Programs	15.00%	13.00%	11.00%
Distributor One
Disaggregation of Revenue [Line Items]
Percentage of revenue from major distributors	32.00%	34.00%	35.00%
Percentage receivables of wholesale distributor accounted in consolidated receivables	27.70%	26.50%
Distributor Two
Disaggregation of Revenue [Line Items]
Percentage of revenue from major distributors	18.00%	21.00%	22.00%
Percentage receivables of wholesale distributor accounted in consolidated receivables	15.60%	19.00%