Commitments and Contingencies - Commitments (Details)								1 Months Ended						3 Months Ended		9 Months Ended
	Jan. 25, 2022 USD ($)	Jan. 25, 2022 EUR (€)	Dec. 22, 2021 USD ($) item	Dec. 22, 2021 EUR (€) item	Oct. 07, 2021 USD ($)	Oct. 07, 2021 EUR (€)	Apr. 06, 2021 USD ($) ft²	Nov. 30, 2022 USD ($) item	Nov. 30, 2022 EUR (€) item	Oct. 31, 2022 USD ($) item	Oct. 31, 2022 EUR (€) item	May 31, 2022 USD ($) item	May 31, 2022 EUR (€) item	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Jan. 26, 2022
Commitments and Contingencies
Lease expense under non-cancelable operating lease	$ 4,200	€ 4,000
Total deposit paid	9,500	9,000
Cash paid for operating lease liabilities recognized under operating cash flows																$ 300,000	$ 384,000
Recognition of operating lease - right-of-use asset and operating lease liability																30,000	223,000
General and administrative expense
Commitments and Contingencies
Lease cost														$ 240,000	$ 45,000	$ 614,000	$ 341,000
If contracts are terminated within 12 months
Commitments and Contingencies
Lease expense under non-cancelable operating lease	$ 4,000	€ 3,817
Office space sub lease
Commitments and Contingencies
Area (in square feet) | ft²							10,526
Extension period							3 years
Lease term							3 years
Monthly base rent for first twelve months							$ 42,000
Monthly base rent for subsequent twelve months							43,000
Monthly base rent for final 12 months							$ 45,000
Leased office premises
Commitments and Contingencies
Extension period																		20 months
Leased vehicle
Commitments and Contingencies
Lease term								48 months	48 months	48 months	48 months
Number of vehicles on lease | item								2	2	3	3
Monthly base rent								$ 1,500	€ 1,459	$ 2,200	€ 2,094
Office lease agreement | Leased office premises
Commitments and Contingencies
Extension period																		20 months
Lease expense under non-cancelable operating lease					$ 10,500	€ 10,000
Total deposit paid					$ 21,000	€ 20,000
Arval Service Lease Italia Spa agreement | Leased vehicle
Commitments and Contingencies
Lease term			48 months	48 months
Lease expense under non-cancelable operating lease			$ 2,100	€ 2,000
Total deposit paid			$ 20,000	€ 19,000
Number of vehicles on lease | item			2	2
Vehicle lease agreement | Leased vehicle
Commitments and Contingencies
Lease term												48 months	48 months
Lease expense under non-cancelable operating lease												$ 880	€ 833
Total deposit paid												$ 22,000	€ 21,000
Number of vehicles on lease | item												1	1