Stock-Based Compensation (Details 9) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Schedule of information on stock units
Undistributed, Beginning Balance	0.9
Granted	0.1
Forfeited	(0.1)
Undistributed, Ending Balance	0.7	[1]
Stock Appreciation Rights [Member]
Schedule of information on stock units
Undistributed, Beginning Balance	2.9
Nonvested, Weighted-Average Exercise Price per Share, Beginning Balance	34.85
Granted	0.4
Granted, Weighted-Average Excercise Price per Share	51.15
Exercised	(1.0)
Exercised, Weighted-Average Exercise Price per Share	31.82
Forfeited	(0.1)
Forfeited, Weighted-Average Exercise Price per Share	37.81
Undistributed, Ending Balance	2.2
Nonvested, Weighted-Average Exercise Price per Share, Ending Balance	38.93
Exercisable at end of year, shares	1.3
Exercisable at end of year, Weighted-Average Exercise Price Per Share	35.75

[1] Undistributed performance share units include approximately 0.5 million units with a weighted-average grant date fair value of $40.31 per share that had not yet vested and 0.2 million units that have vested but were not yet distributed.