Segment Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) item	Sep. 30, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| item			2
Revenue, net	$ 983	$ 1,118	$ 3,132	$ 4,379
Cost of revenue		1,067		3,063
Cost of revenue	826		3,028
Research and development	16,183	15,189	53,334	41,482
Sales and marketing	112	63	629	89
General and administrative	6,726	6,141	21,142	20,481
Goodwill impairment			18,504
Loss from operations	(22,864)	(21,342)	(93,505)	(60,736)
Loss from discontinued operations	(31,875)	(12,108)	(48,360)	(35,640)
Dermatology Therapeutics Segment
Segment Reporting Information [Line Items]
Revenue, net				1,000
Research and development	16,245	15,189	53,585	41,482
Sales and marketing	96	49	581	55
Goodwill impairment			18,504
Loss from operations	(16,341)	(15,238)	(72,670)	(40,537)
Loss from discontinued operations	(30,915)	(11,675)	(45,636)	(35,166)
Contract Research Segment
Segment Reporting Information [Line Items]
Revenue, net	2,943	3,225	11,940	8,779
Cost of revenue		2,823		7,564
Cost of revenue	2,724		11,584
Sales and marketing	16	14	48	34
General and administrative	956	566	2,069	1,557
Loss from operations	(753)	(178)	(1,761)	(376)
Corporate and Other
Segment Reporting Information [Line Items]
Revenue, net	(1,960)	(2,107)	(8,808)	(5,400)
Cost of revenue		(1,756)		(4,501)
Cost of revenue	(1,898)		(8,556)
Research and development	(62)		(251)
General and administrative	5,770	5,575	19,073	18,924
Loss from operations	(5,770)	(5,926)	(19,074)	(19,823)
Loss from discontinued operations	(960)	(433)	(2,724)	(474)
Intersegment Eliminations \| Contract Research Segment
Segment Reporting Information [Line Items]
Revenue, net	$ (1,960)	$ (2,107)	$ 8,807	$ 5,400

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