Shareholders' Equity (Share Repurchase) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended									1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Treasury Stock [Member]	Dec. 31, 2012 Treasury Stock [Member]	Dec. 31, 2011 Treasury Stock [Member]	Dec. 31, 2013 Stock Repurchase Program Board Authorized Repurchases [Member]	Dec. 31, 2012 Stock Repurchase Program Board Authorized Repurchases [Member]	Dec. 31, 2011 Stock Repurchase Program Board Authorized Repurchases [Member]	Jan. 31, 2014 Subsequent Event [Member] Stock Repurchase Program Board Authorized Repurchases [Member]	Feb. 12, 2014 Subsequent Event [Member] Stock Repurchase Program Board Authorized Repurchases [Member]
Class of Stock [Line Items]
Shares repurchased							1.1	16.6	17.1		2.4
Stock Repurchase Program, Authorized Amount										$ 250
Aggregate purchase price	55.7	582.3	584.9	55.7	582.3	584.9	53.5	580.6	583.4		115.7
Average purchase price per share							$ 47.37	$ 34.89	$ 34.14		$ 47.92
Remaining amount available for share repurchase											$ 400.0