Segment Information (Tables)

12 Months Ended

Dec. 31, 2020

Segment Reporting [Abstract]

Schedule of assets and revenues major geographic regions

	Year ended December 31,
Geographic regions	2018			2019			2020
	Amount	%		Amount	%		Amount	%
PRC	146,235	84	%	49,346	64	%	66,160	62	%
India	—	0	%	4,988	7	%	8,570	8	%
Russia	10,869	6	%	3,673	5	%	5,671	5	%
Other countries	236	0	%	7,430	10	%	2,254	2	%
Asia & Pacific	157,340	90	%	65,437	86	%	82,655	77	%
United Kingdom	595	0	%	668	1	%	11,544	11	%
Netherlands	1,621	1	%	1,384	2	%	5,326	5	%
Other countries	14,352	9	%	8,627	11	%	7,444	7	%
Europe	16,568	10	%	10,679	14	%	24,314	23	%
Other	327	0	%	318	0	%	549	0	%
Total	174,235	100	%	76,434	100	%	107,518	100	%