Commitments and Contingencies (Narrative) (Details) - USD ($)	1 Months Ended	9 Months Ended
	Apr. 30, 2020	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Nov. 30, 2022	Nov. 16, 2022	Oct. 28, 2021
Lease term							16 years
Base annual rent for 2024							$ 250,000
Maximum allowance for tenant improvements							7,300,000
Operating lease expected yearly base rent	$ 1,900,000
Annual increase in rent percentage	3.00%
Base rent at the end of lease term	$ 2,500,000
Period of lease and rental abatement credit	6 months
Lease and rental abatement credit	$ 800,000
Operating Lease, Liability	11,700,000					$ 37,000,000.0
Operating Lease, Right-of-Use Asset	$ 11,000,000.0	$ 44,886,000		$ 43,035,000		$ 33,800,000
Lessee, Operating Lease, Discount Rate	12.89%				11.80%
Standby letter of credit							$ 5,000,000.0
Increase (decrease) operating lease right-of-use and liability		$ (9,723,000)	$ 1,457,000
2021 Lease [Member]
Lessee, Operating Lease, Discount Rate		14.27%
Increase (decrease) operating lease right-of-use and liability		$ 2,500,000
Cash [Member]
Standby letter of credit	$ 1,200,000	$ 700,000
Annual reduction of standby letter of credit	20.00%