Share-Based Compensation (Schedule Of Fair Value Of Stock Option Award Granted Estimated On Date Of Grant Using The Black-Scholes-Merton Option Pricing Model) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Share-Based Compensation [Abstract]
Dividend yield
Risk-free interest rate	2.20%	2.50%	2.20%
Weighted average volatility	53.30%	52.40%	55.00%
Expected life (in years)	5.5	5.8	6.5
Weighted average grant date fair value per share of options granted	$ 10.89	$ 14.95	$ 13.48