Commitments and Contingencies - Commitments (Details)									1 Months Ended						12 Months Ended
	Oct. 25, 2023 USD ($) ft²	Jan. 25, 2022 USD ($)	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	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Oct. 24, 2023	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															$ 394,000	$ 315,000
Recognition of operating lease - right-of-use asset and operating lease liability															30,000	365,000
Lease modification															441,000	0
General and administrative expense
Commitments and Contingencies
Lease cost															$ 821,000	$ 629,000
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
Office lease agreement | Suite 400
Commitments and Contingencies
Area (in square feet) | ft²	5,735
Monthly base rent for first two years	$ 18,000
Monthly base rent for third and fourth year	18,000
Monthly base rent for fifth and sixth year	19,000
Monthly base rent for seventh and eighth year	20,000
Monthly base rent for ninth year	$ 21,000
Office lease agreement | Suite 600
Commitments and Contingencies
Area (in square feet) | ft²	5,263
Monthly base rent for remaining term	$ 22,000
Option to extend the lease	true
Office lease agreement | Suite 600 | Minimum
Commitments and Contingencies
Extension period	1 year																1 year
Office lease agreement | Suite 600 | Maximum
Commitments and Contingencies
Extension period	5 years																3 years
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