Stock Option Plans, Shares Reserved and Warrants (Details 3)	Mar. 31, 2019 shares
Reserved shares of common stock for issuance upon exercise	14,958,039
2009 Equity Incentive Plan [Member]
Reserved shares of common stock for issuance upon exercise	8,945,878
RSU [Member]
Reserved shares of common stock for issuance upon exercise	3,877,491
Warrants [Member]
Reserved shares of common stock for issuance upon exercise	2,134,670