CONSOLIDATED BALANCE SHEETS [Parenthetical] (USD $)	Dec. 31, 2011	Dec. 31, 2010
Valuation allowance for other receivables (in dollars)	$ 139,204	$ 272,137
Common Class A [Member]
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized	700,000	700,000
Common stock, shares issued	471,633	478,940
Treasury stock, shares	29,100	36,407
Common Class B [Member]
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	3,742,842	3,530,547
Treasury stock, shares	529,695	570,400