Share-Based Employee Compensation Plans and Other Compensation and Benefit Plans (Restricted Stock Activity) (Details) (Restricted Stock [Member], USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Restricted Stock [Member]
Compensation expense for benefit plans	$ 2,000,000	$ 1,700,000	$ 900,000
Income tax benefit from compensation expense for benefit plans	800,000	600,000	400,000
Total fair value of shares vested (at vest date)	$ 2,700,000	$ 2,600,000	$ 1,600,000
Issuance of common stock under employee benefit plans, net of forfeitures and shares withheld to cover taxes, shares	23,700	49,900	41,100
Average grant-date fair value of shares issued during the period in compensation and benefit plans other than stock options	$ 90.10	$ 56.18	$ 39.57