STOCK-BASED COMPENSATION - 2015 EIP Restricted Stock (Details) - 2015 EIP Plan - Restricted Stock - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2018
Stock Awards
Vesting period of awards	3 years
Number of Shares
Balance at the beginning of the period (in shares)		6,802
Vested (in shares)		(6,802)
Weighted Average Fair Value
Balance at the beginning of the period (in dollars per share)		$ 5.20
Vested (in dollars per share)		$ 5.20
Additional disclosures
Total fair value of shares vested		$ 60
General and Administrative Expense
Additional disclosures
Recognized nonvested stock amortization expense		$ 11

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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