Statements of Stockholders' Equity - USD ($)	Class A Common Stock	Class C Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock	Total
Balance at Dec. 31, 2014	$ 24,918,480	$ 2,788,138	$ 25,931,119	$ 1,438,566	$ 44,101,252	$ (2,086,454)	$ 97,091,101
Net earnings					5,715,982		5,715,982
Other comprehensive income				1,892,537			1,892,537
Grant of stock options			211,476				211,476
Exercise of stock options	27,148	228,046	6,366			(244,009)	17,551
Sale of treasury stock			291,133			240,022	531,155
Stock Dividends	480	2	728		(1,210)
Conversion Class C to Class A	1,064	(1,064)
Balance at Jun. 30, 2015	24,947,172	3,015,122	26,440,822	3,331,103	49,816,024	(2,090,441)	105,459,802
Balance at Dec. 31, 2015	26,218,200	3,419,280	30,232,582	1,533,828	52,021,764	(2,179,429)	111,246,225
Net earnings					7,150,819		7,150,819
Other comprehensive income				869,460			869,460
Grant of stock options			168,478				168,478
Exercise of stock options	56,920		4,367				61,287
Sale of treasury stock			274,184			374,472	648,656
Stock Dividends	274	12,768	30,779		(43,821)
Conversion Class C to Class A	8	(8)
Balance at Jun. 30, 2016	$ 26,275,402	$ 3,432,040	$ 30,710,390	$ 2,403,288	$ 59,128,762	$ (1,804,957)	$ 120,144,925