Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	$ (11.6)	$ (6.4)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(4.6)	(1.8)	(1.1)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax	0.8	(2.9)	1.8
Net unrealized gain or loss on available-for-sale securities	0.2	0.6	6.5
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax	0	(0.1)	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax	(0.1)	(8.3)	0
Other Comprehensive Income (Loss), Net of Tax	(5.2)	(4.2)	3.8
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	(8.7)	(4.1)
Other Comprehensive Income (Loss), Net of Tax	(4.6)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	(3.5)	(2.8)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax	0.1
Other Comprehensive Income (Loss), Net of Tax	(0.7)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	0.6	0.5
Other Comprehensive Income (Loss), Net of Tax	0.1
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	(11.6)	(6.4)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(5.2)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0
Other Comprehensive Income (Loss), Net of Tax	$ (5.2)	$ (4.2)	$ 3.8