FAIR VALUE - RECURRING (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Marketable Securities	$ 110,348	$ 116,748
Recurring
Marketable Securities	110,348	116,748
Available-for-sale Securities
Marketable Securities	110,348	116,748
Corporate
Marketable Securities	15,478	20,064
Corporate | Recurring
Marketable Securities	15,478	20,064
Corporate | Level 2 | Recurring
Marketable Securities	14,978	19,564
Corporate | Level 3 | Recurring
Marketable Securities	500	500
US Agencies
Marketable Securities	22,194	15,970
US Agencies | Recurring
Marketable Securities	22,194	15,970
US Agencies | Level 2 | Recurring
Marketable Securities	22,194	15,970
US Agencies - MBS
Marketable Securities	29,574	32,840
US Agencies - MBS | Recurring
Marketable Securities	29,574	32,840
US Agencies - MBS | Level 2 | Recurring
Marketable Securities	29,574	32,840
Obligations of states and political subdivisions
Marketable Securities	43,102	47,874
Obligations of states and political subdivisions | Recurring
Marketable Securities	43,102	47,874
Obligations of states and political subdivisions | Level 2 | Recurring
Marketable Securities	42,172	46,886
Obligations of states and political subdivisions | Level 3 | Recurring
Marketable Securities	$ 930	$ 988