SHARE-BASED COMPENSATION - Nonvested Restricted Shares - (Details) - Kaixin Auto 2019 Plan - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
May 03, 2019	Dec. 31, 2020	Dec. 31, 2019
Weighted average fair value per ordinary shares at the granted dates
Weighted average period for unrecognized compensation cost		1 year 2 months 26 days
Restricted Stock
Number of nonvested restricted shares
Balance at the beginning of period		1,446,111
Granted	2,183,828	200,000
Vested		(474,889)
Forfeited		(13,232)
Balance at the end of period		1,157,990	1,446,111
Weighted average fair value per ordinary shares at the granted dates
Balance at the beginning of period		$ 3.36
Granted		4.73
Forfeited		3.94
Balance at the end of period		$ 3.36	$ 3.36
Total unrecognized compensation cost		$ 199
Weighted average period for unrecognized compensation cost		7 months 24 days
Total fair value of shares vested		$ 1,870	$ 3,231

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Net number of non-option equity instruments granted to participants.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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