Dividends (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	0 Months Ended	3 Months Ended		6 Months Ended		0 Months Ended
	Sep. 04, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Oct. 30, 2014 Subsequent Event [Member]
Dividends [Abstract]
Dividend per share paid during period	$ 0.356			$ 0.7115
Cash Dividend	$ 71.4			$ 142.6		$ 71.7
Subsequent Event [Line Items]
Dividends declared per common share		$ 0.3560	$ 0.3540	$ 0.7115	$ 0.7075	$ 0.3565
Total amount of expected dividend payment	$ 71.4			$ 142.6		$ 71.7