Leases - Schedule of Right-of-Use Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Lessee Lease Description [Line Items]
Right-of-use assets	$ 1,353	$ 1,483
Lease liabilities	1,385
Del Mar, CA [Member]
Lessee Lease Description [Line Items]
Right-of-use assets	710
Lease liabilities	711
Burlingame, CA [Member]
Lessee Lease Description [Line Items]
Right-of-use assets	321
Lease liabilities	352
Edwardsville, IL [Member]
Lessee Lease Description [Line Items]
Right-of-use assets	322
Lease liabilities	$ 322