INVESTMENTS (Details Textual) - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Aug. 31, 2018	May 31, 2018	Dec. 31, 2017
Schedule Of Investments [Line Items]
Long-term Investments	$ 5,425,000			$ 5,000,000	$ 0
Private Equity Investment Commitment			$ 5,000,000
Private Equity Investment Purchase	425,000
Cost					50,681,000
Trading Securities, Unrealized Holding Gain		$ 678,000
Trading Securities, Unrealized Holding Loss		(35,000)
Estimated Market Value	71,003,000				51,324,000
VIE
Schedule Of Investments [Line Items]
Estimated Market Value	8,700,000				10,700,000
U.S. Government and Government agency obligations
Schedule Of Investments [Line Items]
Cost	51,194,000				29,367,000
Trading Securities, Unrealized Holding Gain	117,000	21,000
Trading Securities, Unrealized Holding Loss	0	(15,000)
Estimated Market Value	51,311,000				29,373,000
Money market funds
Schedule Of Investments [Line Items]
Cost	9,978,000				9,736,000
Trading Securities, Unrealized Holding Gain	0	0
Trading Securities, Unrealized Holding Loss	0	0
Estimated Market Value	9,978,000				9,736,000
Equity funds
Schedule Of Investments [Line Items]
Cost	9,333,000				11,578,000
Trading Securities, Unrealized Holding Gain	545,000	657,000
Trading Securities, Unrealized Holding Loss	(164,000)	$ (20,000)
Estimated Market Value	9,714,000				$ 12,215,000
Private Equity Funds [Member]
Schedule Of Investments [Line Items]
Cost	70,505,000
Trading Securities, Unrealized Holding Gain	662,000
Trading Securities, Unrealized Holding Loss	(164,000)
Estimated Market Value	$ 71,003,000