SENIOR UNSECURED DEBT (Schedule of Senior Unsecured Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Feb. 22, 2017	Oct. 18, 2016
Debt Instrument [Line Items]
Senior unsecured debt	$ 118,958	$ 118,382
Senior Notes
Debt Instrument [Line Items]
Senior unsecured debt	118,958	118,382
Senior Notes | Senior Notes Due 2026
Debt Instrument [Line Items]
Senior unsecured debt	51,287	51,011
Debt instrument, unamortized discount (premium) and debt issuance costs	2,308	2,584		$ 3,800
Senior Notes | Senior Notes Due 2024
Debt Instrument [Line Items]
Senior unsecured debt	67,671	67,371
Debt instrument, unamortized discount (premium) and debt issuance costs	$ 1,329	$ 1,629	$ (2,800)