Rights Plan and Series A Junior Participating Preferred Stock (Narrative) (Details) (USD $)	Dec. 31, 2011	Dec. 31, 2010	Jan. 31, 2004	Sep. 10, 2002
Rights Plan and Series A Junior Participating Preferred Stock [Abstract]
Preferred stock, shares designated as Series A Junior Participating Preferred Stock	700,000	700,000		700,000
Preferred stock, shares authorized	5,000,000	5,000,000		5,000,000
Preferred stock, par value per share	$ 0.01	$ 0.01		$ 0.01
Per share price for registered holders				$ 9.00
Amendment to rights plan per share purchase price			$ 65.00