Share-Based Employee Compensation Plans and Other Compensation and Benefit Plans (Stock Option Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
Employee Stock Option [Member]
Vesting of options, description	The Company's employee incentive plans provide for the granting of stock options for the purchase of the common stock of the Company to certain key employees of the Company. Employee stock options are granted at an exercise price that is equal to the closing market price of the Company's common stock on the date of the grant.
Options expiration date, years	ten
Options vesting period	four
Option vesting rate per year	25.00%
Stock Option [Member]
Remaining unrecognized compensation expense	39.6
Weighted-average period for cost recognition, years	2.8
Stock Option [Member] | Director [Member]
Vesting of options, description	The Company's director stock plan provides for the granting of stock options for the purchase of the common stock of the Company to directors of the Company. Director stock options are granted at an exercise price that is equal to the closing market price of the Company's common stock on the date of the grant.
Options expiration date, years	seven
Options vesting period	six