Stock-Based Compensation Plans (Schedule Of Future Share-Based Compensation Cost) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remainder of 2012	$ 3,207
2013	10,710
2014	7,613
2015	6,327
2016	5,501
Thereafter	15,782
Total	49,140
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remainder of 2012	913
2013	3,086
2014	2,350
2015	2,029
2016	1,862
Thereafter	8,722
Total	18,962
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remainder of 2012	2,294
2013	7,624
2014	5,263
2015	4,298
2016	3,639
Thereafter	7,060
Total	$ 30,178

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