INCOME TAXES - Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
U.S. federal corporate income tax rate	21.00%	21.00%	35.00%
Income tax provision/(benefit)
New tax law benefit		$ 2,000
Total income tax provision/(benefit)	$ 3,838	688	$ (240)
TRS
Income tax provision/(benefit)
U.S. federal income tax provision/(benefit)	2,905	321	581
State income tax provision	1,013	527	493
Other items	(139)	(167)	(188)
New tax law benefit			(1,129)
ITC basis adjustment	56
Valuation allowance	3	7	3
Total income tax provision/(benefit)	$ 3,838	$ 688	$ (240)