Income Taxes - Components Of Company's deferred Tax Asset (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred Tax Assets, Net of Valuation Allowance [Abstract]
Accrued bonuses	$ 64	$ 12
Accrued vacation	16	15
Net operating loss (NOL) carryover	10,789	9,191
Technology licenses amortization	0	0
Research & development tax credits	2,070	1,780
Share based expense	401	310
Other	4	5
Fixed asset depreciation	61	50
Total deferred tax asset	13,405	11,363
Less: valuation allowance	(13,405)	(11,363)
Net deferred tax asset	0	0
Deferred tax liability- non-current	0	0
Net deferred tax asset	$ 0	$ 0