Debt - 2019 Exchange Notes (Details)	1 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2019 USD ($) item	Jul. 31, 2019 USD ($) shares	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2016 USD ($)
Convertible Promissory Notes and Common Stock Warrants [Line Items]
Principal amount							$ 12,500,000
Loss on extinguishment of debt			$ (2,663,000)	$ (4,605,000)
Exchange Notes
Convertible Promissory Notes and Common Stock Warrants [Line Items]
Number of Napo convertible notes | item	2
Number of Napo convertible notes exchanged for CVP note | item	2
Convertible debt payable					$ 6,678,000	$ 6,678,000
2019 Exchange Note 1
Convertible Promissory Notes and Common Stock Warrants [Line Items]
Principal amount	$ 10,125,000
Principal amount and accrued interest	10,536,000
Accrued interest on notes payable	$ 411,000
Interest rate (as a percent)	10.00%
Common stock issued in exchange of debt | shares		1,119,440
Convertible debt payable					$ 4,381,000	4,381,000
Repayments of notes payable, principal		$ 6,154,000
Repayments of notes payable, interest		$ 90,000
Share issued for principal and interest payment | shares		1,119,440
2019 Exchange Note 2
Convertible Promissory Notes and Common Stock Warrants [Line Items]
Principal amount	$ 2,297,000
Interest rate (as a percent)	10.00%
Convertible debt payable						$ 2,297,000