OTHER INVESTMENTS (Details 1) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair Value
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 215,000	$ 273,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	132,000	132,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	347,000	405,000
Unrealized
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	(17,000)	(27,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	(18,000)	(18,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	(35,000)	(45,000)
Partnerships Owning Investments In Technology Related Industries [Member]
Fair Value
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	132,000	132,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	132,000	132,000
Unrealized
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	(18,000)	(18,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	(18,000)	(18,000)
Partnerships owning diversified businesses investments [Member]
Fair Value
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	215,000	273,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	215,000	273,000
Unrealized
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	(17,000)	(27,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	$ (17,000)	$ (27,000)

Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract]

No definition available.

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

No definition available.

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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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