Indebtedness - Non-current asset on the balance sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Indebtedness
Current	$ 65	$ 57
Non current	150	221
NEBT Loan
Indebtedness
Current	8	13
Non current	24	31
RETOS 2015
Indebtedness
Current	57	44
Non current	$ 126	$ 190

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant