Equity Narratives (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Oct. 28, 2015
Equity, Class of Treasury Stock [Line Items]
Dividends declared per share		$ 0.12	$ 0.09	$ 0.32	$ 0.25
Dividends, Common Stock, Cash				$ 23.7
Treasury Stock, Shares, Acquired		11,008,576			0
Treasury Stock, Value, Acquired, Par Value Method				$ 305.5
Treasury Stock Acquired, Average Cost Per Share				$ 27.75
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 321.6		$ 321.6
Subsequent Event [Member]
Equity, Class of Treasury Stock [Line Items]
Treasury Stock, Shares, Acquired	619,905
Treasury Stock, Value, Acquired, Par Value Method	$ 17.5
Treasury Stock Acquired, Average Cost Per Share	$ 28.17
Stock Repurchase Program, Remaining Authorized Repurchase Amount						$ 304.1