Equity And Stock-Based Compensation (Schedule Of Stock Options Outstanding And Exercisable) (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Equity And Stock-Based Compensation [Line Items]
Weighted Average Exercise Price of Options Outstanding, Granted	$ 12.34	$ 7.40
Class A [Member]
Equity And Stock-Based Compensation [Line Items]
Common Stock Options Outstanding, Beginning balance	568,250	709,850	709,850
Common Stock Options Outstanding, Granted	12,000	20,000	80,000
Common Stock Options Outstanding, Exercised	(47,500)		(157,600)
Common Stock Options Outstanding, Expired			(64,000)
Common Stock Options Outstanding, Ending balance	532,750		568,250
Weighted Average Exercise Price of Options Outstanding, Beginning price	$ 6.88	$ 6.88	$ 6.88
Weighted Average Exercise Price of Options Outstanding, Granted	$ 12.34		$ 8.56
Weighted Average Exercise Price of Options Outstanding, Exercised	$ 6.87		$ 6.21
Weighted Average Exercise Price of Options Outstanding, Expired			$ 6.83
Weighted Average Exercise Price of Options Outstanding, Ending price	$ 7.01		$ 6.88
Common Stock Exercisable Options, Outstanding Beginning balance	348,000	490,350	490,350
Common Stock Exercisable Options, Outstanding Ending balance	313,750		348,000
Weighted Average Price of Exercisable Options, Outstanding Beginning balance	$ 6.82	$ 6.85	$ 6.85
Weighted Average Price of Exercisable Options, Outstanding Ending balance	$ 7.02		$ 6.82
Class B [Member]
Equity And Stock-Based Compensation [Line Items]
Common Stock Options Outstanding, Beginning balance	185,100	185,100	185,100
Common Stock Options Outstanding, Granted
Common Stock Options Outstanding, Ending balance	185,100		185,100
Weighted Average Exercise Price of Options Outstanding, Beginning price	$ 9.90	$ 9.90	$ 9.90
Weighted Average Exercise Price of Options Outstanding, Granted
Weighted Average Exercise Price of Options Outstanding, Ending price	$ 9.90		$ 9.90
Common Stock Exercisable Options, Outstanding Beginning balance	185,100	185,100	185,100
Common Stock Exercisable Options, Outstanding Ending balance	185,100		185,100
Weighted Average Price of Exercisable Options, Outstanding Beginning balance	$ 9.90	$ 9.90	$ 9.90
Weighted Average Price of Exercisable Options, Outstanding Ending balance	$ 9.90		$ 9.90