Stock-Based Compensation And Employee Stock Option Plan (Schedule Of Stock Options Outstanding And Exercisable) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Class A [Member]	Dec. 31, 2012 Class A [Member]	Dec. 31, 2010 Class A [Member]	Dec. 31, 2013 Class B [Member]	Dec. 31, 2012 Class B [Member]	Dec. 31, 2011 Class B [Member]	Dec. 31, 2010 Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock Options Outstanding, Beginning balance			672,350	622,350	622,350	185,100	185,100	185,100	185,100
Common Stock Options Outstanding, Granted			175,000	206,000
Common Stock Options Outstanding, Exercised			(137,500)	(136,000)
Common Stock Options Outstanding, Expired				(20,000)
Common Stock Options Outstanding, Ending balance			709,850	672,350	622,350	185,100	185,100	185,100	185,100
Weighted Average Exercise Price of Options Outstanding, Beginning price			$ 6.24	$ 5.65	$ 5.65	$ 9.90	$ 9.90	$ 9.90	$ 9.90
Weighted Average Exercise Price of Options Outstanding, No activity				$ 5.94
Weighted Average Exercise Price of Options Outstanding, Granted	$ 6.19	$ 5.94	$ 6.19
Weighted Average Exercise Price of Options Outstanding, Exercised			$ 4.00	$ 4.68
Weighted Average Exercise Price of Options Outstanding, Expired				$ 3.75
Weighted Average Exercise Price of Options Outstanding, Ending price			$ 6.66	$ 6.24	$ 5.65	$ 9.90	$ 9.90	$ 9.90	$ 9.90
Common Stock Exercisable Options, Outstanding Beginning balance			546,350	544,383	449,750	185,100	185,100	167,550	150,000
Common Stock Exercisable Options, Outstanding Ending balance			490,350	546,350	449,750	185,100	185,100	167,550	150,000
Weighted Average Price of Exercisable Options, Outstanding Beginning balance			$ 6.26	$ 5.86	$ 6.22	$ 9.90	$ 9.90	$ 10.05	$ 10.24
Weighted Average Price of Exercisable Options, Outstanding Ending balance			$ 6.85	$ 6.26	$ 6.22	$ 9.90	$ 9.90	$ 10.05	$ 10.24