Notes Payable, Preferred Stock and Stock Purchase Warrants - Interest expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Long term debt
Interest	$ 1,771	$ 2,180
Debt Discount & Fees	2,217	1,891
Issuance Costs	67	58
Loss on extinguishment	3,183
Final Payment Fee		240
Total Interest Expense	$ 7,238	$ 4,369
Solar Term Loan
Long term debt
Effective Interest Rate		8.98%
Interest		$ 887
Debt Discount & Fees		139
Issuance Costs		36
Final Payment Fee		240
Total Interest Expense		$ 1,302
2023 Notes
Long term debt
Effective Interest Rate	5.25%	5.25%
Interest	$ 206	$ 1,087
Debt Discount & Fees	303	1,476
Issuance Costs		22
Total Interest Expense	$ 509	$ 2,585
2025 Notes
Long term debt
Effective Interest Rate	5.25%	5.25%
Interest	$ 757	$ 206
Debt Discount & Fees	1,110	276
Issuance Costs	18
Loss on extinguishment	3,183
Total Interest Expense	$ 5,068	$ 482
PHC Notes
Long term debt
Effective Interest Rate	9.50%
Interest	$ 794
Debt Discount & Fees	804
Issuance Costs	49
Total Interest Expense	$ 1,647
PPP Loan
Long term debt
Effective Interest Rate	1.00%
Interest	$ 14
Total Interest Expense	$ 14