Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Consolidated Statements of Comprehensive Income
Unrealized appreciation on securities, income taxes	$ 34.2	$ 37.2	$ 11.0
Reclassification of realized gains in net income, income taxes	(60.8)
Minimum pension liability adjustments, income taxes	$ 6.6	$ 2.4	$ (2.2)