Stock-Based Compensation Plans (Summary Of Stock Option Activity) (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, at beginning of period, Number of Shares	2,513,327
Options outstanding, at beginning of period, Weighted-Average Exercise Price (in dolars per share)	$ 30.03
Options granted, Number of Shares	398,616
Options granted, Weighted-Average Exercise Price (in dolars per share)	$ 23.81
Options exercised, Number of Shares	77,539
Options exercised, Weighted-Average Exercise Price (in dolars per share)	$ 12.85
Options forfeited or expired, Number of Shares	357,759
Options forfeited or expired, Weighted-Average Exercise Price (in dolars per share)	$ 34.02
Options outstanding, at end of period, Number of Shares	2,476,645
Options outstanding, at end of period, Weighted-Average Exercise Price (in dolars per share)	$ 28.99
Options exercisable, at end of period, Number of Shares	2,068,845
Options exercisable, at end of period, Weighted-Average Exercise Price (in dolars per share)	$ 30.15
Options expected to vest, at end of period, Number of Shares	372,758
Options expected to vest, at end of period, Weighted-Average Exercise Price (in dolars per share)	$ 23.12