Schedule of Geographic Area Information (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Total revenues		$ 1,826	$ 3,515
Long-lived assets		5,630	8,175
UNITED STATES
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Total revenues		1,160	2,092
Foreign [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Total revenues	[1]	666	1,423
Long-lived assets	[2]	4,595	4,521
Domestic [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Long-lived assets		$ 1,035	$ 3,654

[1] Foreign revenues are primarily generated from grants in Israel.

[2] Assets in foreign countries principally include laboratory equipment and leasehold improvements in Israel.