Income Taxes (Schedule Of Reconciliation Of The U.S. Federal Statutory Rate To Effective Tax Rate) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Income Taxes [Abstract]
U.S. federal statutory rate	35.00%	35.00%	35.00%	35.00%
State income taxes	2.60%	2.60%	1.60%	2.20%
Changes in reserve for uncertain tax positions as a result of settlements and lapsed statutes and related interest	(0.60%)	(0.60%)	(0.40%)	(0.80%)
Other	(0.50%)	(0.50%)	0.20%	(0.20%)
Effective tax rate	36.50%	36.50%	36.40%	36.20%