Marketable Securities (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 654,000		$ 654,000		$ 654,000
Gains in Accumulated Other Comprehensive Income (Loss)	0		0		0
Losses in Accumulated Other Comprehensive Income (Loss)	(198,000)		(198,000)		(219,000)
Estimated Fair Value	456,000		456,000		435,000
Proceeds from sales of marketable securities	0	$ 0	0	$ 496,000
Gain on sale of marketable securities	44,000		0	44,000
Net unrealized holding loss on available-for-sale securities			(198,000)	$ (240,000)
Real Estate Common Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	654,000		654,000		654,000
Gains in Accumulated Other Comprehensive Income (Loss)	0		0		0
Losses in Accumulated Other Comprehensive Income (Loss)	(198,000)		(198,000)		(219,000)
Estimated Fair Value	$ 456,000		$ 456,000		$ 435,000