Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended		60 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jul. 27, 2015
Dividends declared	$ 3.3	$ 3.3
Dividends paid	$ 3.2	$ 3.2
Dividends Payable, Date Declared	Jul. 27, 2015
Subsequent Event [Member]
Monthly cash dividends declared, per common share			$ 1.98
Dividends declared				$ 0.5