4. Investments in Marketable Securities (Detail) - (Table 1) Table of Investments in Marketable Securities (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Fair Value	$ 2,158,330	$ 2,019,476
Unrealized Gain (loss)	86,000	(189,000)
Real Estate Investment Trusts [Member]
Cost Basis	174,000	231,000
Fair Value	122,000	154,000
Unrealized Gain (loss)	(52,000)	(77,000)
Mutual Funds [Member]
Cost Basis	760,000	418,000
Fair Value	817,000	457,000
Unrealized Gain (loss)	57,000	39,000
Equity Securities, Other [Member]
Cost Basis	570,000	532,000
Fair Value	557,000	523,000
Unrealized Gain (loss)	(13,000)	(9,000)
Equity Securities [Member]
Cost Basis	1,504,000	1,181,000
Fair Value	1,496,000	1,134,000
Unrealized Gain (loss)	(8,000)	(47,000)
Debt Securities [Member]
Cost Basis	621,000	889,000
Fair Value	662,000	885,000
Unrealized Gain (loss)	41,000	(4,000)
Total [Member]
Cost Basis	2,125,000	2,070,000
Fair Value	2,158,000	2,019,000
Unrealized Gain (loss)	$ 33,000	$ (51,000)