Amount Due to an Affiliate (Details) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020
Amount Due To Affiliate
Payment made by Sinsin on behalf of the Group		$ 10,603	$ 9,563
Borrowing from Sinsin, current	[1]	0	193
Borrowing from Sinsin, noncurrent	[1]	0	832
Total amount due to an affiliate		$ 10,603	$ 10,588

[1] On February 20, 2019 and October 14, 2019, the Group borrowed $729 (EUR 650) and $1,308 (EUR 1,165) from Sinsin, with interest rates of 5% and 4.5% per annum, which will mature on December 31, 2024 and 2027, respectively. As of December 31, 2021, both of the loans have been repaid.