Stock Benefit Plans and Equity Transactions - Summary Common Stock Reserved for Future Issuance (Details) shares in Thousands	Sep. 30, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	50,312
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	4,141
Unvested Restricted Stock Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	8,072
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	394
Series A Convertible Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	29
Warrants Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	25,358
Authorized for Future Grant Under the Distributor and Development Services Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	6,783
Authorized for Future Grant Under the Management Objective Strategic Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	345
Authorized for Future Grant Under the Company Equity Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	5,190