OTHER CURRENT LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Other Liabilities Disclosure [Abstract]
Accrued capital costs	$ 17,035	$ 80,696
Accrued finance lease liability	1,989
Accrued incentive compensation	1,425	468
Accrued operations and maintenance expense	1,520	2,863
Accrued taxes other than income	689	69
Operating lease liability - current	602
Accrued interest	462	232
Other	203	598
Total other current liabilities	$ 23,925	$ 84,926