Guarantee Arrangements (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Customer obligation guarantees
Guarantee Obligations
Guarantee obligations, maximum exposure	$ 365.7		$ 365.7
Aggregate amount of indebtedness which the Company is a party to through guarantee agreements	89.2		89.2
Changes in provision for loss on customer guarantees
Balance at beginning of period	4.7	4.7	5.0	6.5
Provision for new credit guarantees	0.4	0.5	0.4	0.7
Settlements made	0	0	(0.1)	(0.5)
Changes for pre-existing guarantees, net	(0.2)	(0.6)	(0.3)	(1.7)
Amortization of previous guarantees	(0.1)	(0.1)	(0.2)	(0.5)
Foreign currency translation	0	0.1	0	0.1
Balance at end of period	4.8	4.6	4.8	4.6
Loss pool agreements
Guarantee Obligations
Aggregate amount of indebtedness which the Company is a party to through guarantee agreements	$ 128.0		$ 128.0