Income Taxes (Schedule Of Reconciliation Of The U.S. Federal Statutory Rate To Effective Tax Rate) (Details)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Income Taxes [Abstract]
U.S. federal statutory rate	35.00%	35.00%
State income taxes	1.40%	1.40%
Changes in reserve for uncertain tax positions as a result of settlements and lapsed statutes and related interest	(0.30%)	(0.40%)
Other	0.20%	0.10%
Effective tax rate	36.30%	36.10%