Legal Proceedings, Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Nov. 13, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability, current		$ 306		$ 306
Operating lease liability, non-current		0		0
Operating lease right-of-use asset		$ 306		$ 306
Operating lease, discount rate		13.00%		13.00%
Operating lease, remaining term				1 year
Rent expense, Topic 842		$ 100		$ 300
Rent expense, Topic 840			$ 100		$ 300
Operating lease amortization		$ 100		$ 200
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability, current						$ 400
Operating lease liability, non-current						200
Operating lease right-of-use asset						$ 600
Class Action Complaints | Subsequent Event
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Period to file amended complaint	30 days