Commitments And Contingencies (Narrative) (Details)		1 Months Ended	3 Months Ended
	May 13, 2021 USD ($)	Jun. 30, 2021 USD ($) $ / shares	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 11, 2021 USD ($)	May 31, 2019 ft²	Jan. 31, 2017 ft²	Dec. 31, 2014 $ / shares
Commitments and Contingencies [Line Items]
Director and officer insurance premium payable	$ 2,600,000
Insurance down payment	700,000
Financed insurance policy balance	$ 1,900,000
Financed insurance policy interest rate	3.69%
Rent expense, including common area maintenance charges			$ 500,000	$ 500,000
MDB Capital Group, LLC [Member] | Private Placement [Member]
Commitments and Contingencies [Line Items]
Price per share | $ / shares								$ 2.67
Robert W. Duggan [Member] | Private Placement [Member]
Commitments and Contingencies [Line Items]
Principal sum		$ 41,000,000.0
Accrued interest		$ 600,000
Price per share | $ / shares		$ 16.40
Hayward, CA [Member]
Commitments and Contingencies [Line Items]
Lease term							5 years
Area Of Lease | ft²							15,700
Lease Amendment [Member]
Commitments and Contingencies [Line Items]
Area Of Lease | ft²						13,300
Expansion Premises [Member]
Commitments and Contingencies [Line Items]
Area Of Lease | ft²						21,300
Loan Agreement [Member] | Robert W. Duggan [Member]
Commitments and Contingencies [Line Items]
Principal sum					$ 41,000,000.0
Debt instrument, quarterly interest rate					5.00%
Accrued interest				$ 100,000