Post-effective amendment to a registration statement that is not immediately effective upon filing

PROPERTY AND EQUIPMENT,NET - Depreciation expense (Details)

v3.21.1
PROPERTY AND EQUIPMENT,NET - Depreciation expense (Details) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
PROPERTY AND EQUIPMENT, NET      
Depreciation expense $ 2,139,000 $ 2,223,000 $ 2,121,000
Discontinued operations      
PROPERTY AND EQUIPMENT, NET      
Depreciation expense     $ 41,000