Accounts Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, gross	$ 8,619	$ 2,405
Less: allowance for doubtful accounts	(1,219)
Accounts receivable, net	7,400	2,405
Changes in the allowance for doubtful accounts	(1,219)	0
Guizhou Qianxi Green Environmentally Friendly Taxi Service Co
Accounts, Notes, Loans and Financing Receivable [Line Items]
Changes in the allowance for doubtful accounts	1,200
Taxi Commission Revenue Receivables	$ 1,200	$ 2,300