Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2012		Dec. 31, 2011		Mar. 31, 2011
Class A Common Stock [Member]
Common stock, par value	$ 1	[1]	$ 1	[2]	$ 1	[1]
Common stock, shares issued	8,644,307	[1]	8,644,307	[2]	8,756,778	[1]
Common stock, shares outstanding	8,644,307	[1]	8,644,307	[2]	8,756,778	[1]
Class B Common Stock [Member]
Common stock, par value	$ 1	[1]	$ 1	[2]	$ 1	[1]
Common stock, shares issued	1,631,424	[1]	1,639,812	[2]	1,677,675	[1]
Common stock, shares outstanding	1,631,424	[1]	1,639,812	[2]	1,677,675	[1]

[1] Unaudited

[2] Derived from 2011 Annual Report on Form 10-K.