Accumulated Other Comprehensive Income (Loss) Rollforward (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax	$ 0.0
Accumulated other comprehensive loss, net	(22.9)		$ (17.5)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax	0.0
Other comprehensive loss	(5.4)	$ 0.8
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	(18.3)		(12.7)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(5.6)
Other comprehensive loss	(5.6)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax	0.4
Accumulated other comprehensive loss, net	(4.6)		(4.8)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(0.2)
Other comprehensive loss	0.2
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	0.0		0.0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0.0
Other comprehensive loss	0.0
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss, net	(22.9)		$ (17.5)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(5.8)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.4
Other comprehensive loss	$ (5.4)