Common Stock (Details) (USD $)	9 Months Ended	0 Months Ended	9 Months Ended		9 Months Ended
	Sep. 30, 2014	May 16, 2014 May 2014 Stock Repurchase Plan [Member]	Sep. 30, 2014 May 2014 Stock Repurchase Plan [Member]	May 14, 2004 May 2004 Stock Repurchase Plan [Member]	Sep. 30, 2014 Executive Officer [Member] Class A Nonvoting Common Stock [Member]	Sep. 30, 2013 Executive Officer [Member] Class A Nonvoting Common Stock [Member]
Common Stock [Line Items]
Stocks granted					125,209	217,890
Repurchase program, amount authorized		$ 10,000,000
Repurchase program, shares authorized				350,000
Repurchase program, amount repurchased	2,342,000
Repurchase program, remaining amount authorized			$ 7,700,000