Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Revenue	$ 0	$ 0	$ 40	$ 41
Cost of revenue	0	0	11	24
Gross profit	0	0	29	17
Operating expenses:
Selling, general and administrative	1,238	1,363	3,667	4,397
Research and development	1,026	1,495	3,027	4,721
Total operating expenses	2,264	2,858	6,694	9,118
Loss from operations	(2,264)	(2,858)	(6,665)	(9,101)
Interest and other income, net	12	3	15	103
Loss before income taxes	(2,252)	(2,855)	(6,650)	(8,998)
Income tax benefit	858	0	858	0
Net loss	$ (1,394)	$ (2,855)	$ (5,792)	$ (8,998)
Weighted average common shares outstanding:
Basic and diluted	5,467	4,060	4,734	4,059
Basic and diluted net loss per common share:
Net loss	$ (0.25)	$ (0.70)	$ (1.22)	$ (2.22)
Other comprehensive loss, net of tax:
Net loss	$ (1,394)	$ (2,855)	$ (5,792)	$ (8,998)
Available-for-sale securities:
Net unrealized gain		(32)		(67)
Reclassification adjustment for realized loss	0	42	31	76
Total comprehensive loss	$ (1,394)	$ (2,845)	$ (5,761)	$ (8,989)