Stock-Based Compensation (Stock Option Activity) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding at beginning of period	1,192,670
Granted	0
Exercised	(458,603)
Forfeitured and expired	(10,370)
Options outstanding and exercisable at end of period	723,697
Weighted Average Exercise Price Per Share - Options outstanding at beginning of period	$ 41.86
Weighted Average Exercise Price Per Share - Granted	$ 0.00
Weighted Average Exercise Price Per Share - Exercised	$ 40.71
Weighted Average Exercise Price Per Share - Forfeitured or expired	$ 41.46
Weighted Average Exercise Price Per Share - Options outstanding and exercisable at end of period	$ 42.60
Aggregate Intrinsic Value - Options outstanding and exercisable at end of period	$ 18