Fair Value Measurements (Reconciliation Of The Credit Loss Recognized On Tax Increment Revenue Bonds) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2011
Fair Value Measurements [Abstract]
Beginning balance	$ 31,022	$ 11,717
Additions		19,305
Ending balance	$ 31,022	$ 31,022