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Stock-Based Compensation - Additional Information (Details) - USD ($)				1 Months Ended				3 Months Ended		6 Months Ended
	Sep. 05, 2019	Sep. 07, 2017	May 15, 2015	Sep. 24, 2018	Aug. 25, 2016	Oct. 22, 2013	Mar. 20, 2007	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Nov. 02, 2010
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures								0	0	0	0
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options								$ 498,000		$ 498,000
Employees \| General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense								40,000	$ 50,000	79,000	$ 106,000
Employees \| Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense								15,000	32,000	31,000	110,000
Consultants \| General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense								27,000	9,000	53,000	19,000
Consultants \| Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award
Allocated Share-based Compensation Expense								$ 4,000	$ 1,000	$ 6,000	$ 1,000
2007 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number							71,429	7,052		7,052
2007 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross							7,143
2010 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number								2,465,310		2,465,310		85,714
2010 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	4,000,000	500,000	228,572	1,000,000	400,000	171,429
2010 Stock Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	1,000,000	400,000	171,429	500,000	228,572	85,714