Consolidated Statement of Stockholders' Equity (Unaudited) (USD $)	Total	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Retained Earnings	Treasury Stock	Common Class A	Common Class B
Beginning balance at Dec. 31, 2011	$ 383,451,592	$ 170,836,943	$ 23,533,447	$ 199,604,700	$ (10,787,520)	$ 207,530	$ 56,492
Beginning balance, shares at Dec. 31, 2011						20,752,999	5,649,240
Issuance of common stock (stock compensation plans)	2,308,373	2,306,886				1,487
Issuance of common stock (stock compensation plans), shares						148,670
Net income	16,872,598			16,872,598
Cash dividends declared	(6,141,281)			(6,141,281)
Grant of stock options		40,726		(40,726)
Tax benefit on exercise of stock options	49,517	49,517
Repurchase of treasury stock	(1,349,380)				(1,349,380)
Other comprehensive income	7,697,166		7,697,166
Other			(1,783,457)	1,783,457
Ending balance at Sep. 30, 2012	$ 402,888,585	$ 173,234,072	$ 29,447,156	$ 212,078,748	$ (12,136,900)	$ 209,017	$ 56,492
Ending balance, shares at Sep. 30, 2012						20,901,669	5,649,240