LIABILITY FOR EMPLOYEE RIGHTS UPON RETIREMENT (Details)	12 Months Ended
	Dec. 31, 2020 USD ($) employee	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Employee severance obligation payments	$ 121,000	$ 143,000	$ 145,000
Contributions	747,000	642,000	620,000
Severance expense	885,000	784,000	781,000
Gain for the period	28,000	$ 58,000	$ 46,000
Benefits Payable During Next Five Years	$ 73,000
Number of benefit eligible employees | employee	3
Contribution to Insurance Companies [Member]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 975,000
Contribution to Defined Contribution Plans [Member]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 864,000