Business Restructuring and Cost Reduction Actions (Carrying Amount of Accrual) (Details) - USD ($) $ in Millions	3 Months Ended																	12 Months Ended
	Sep. 30, 2015		Jun. 30, 2015	[1]	Mar. 31, 2015	[1]	Dec. 31, 2014	[1]	Sep. 30, 2014		Jun. 30, 2014	[1]	Mar. 31, 2014	[1]	Dec. 31, 2013	[1]	Sep. 30, 2013	Sep. 30, 2015		Sep. 30, 2014		Sep. 30, 2013
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions	$ 61.7	[1]	$ 58.2		$ 55.4		$ 32.4		$ 12.7	[1]	$ 0.0		$ 0.0		$ 0.0			$ 207.7	[1]	$ 12.7	[1]	$ 231.6
Business Realignment and Reorganization [Member]
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions									12.7									207.7		12.7
Amount reflected in pension liability																		(14.0)		0.0
Noncash expenses																		(47.4)
Cash expenditures																		(114.7)		(2.2)
Currency translation adjustment																		(0.4)		0.0
Accrued Balance	41.7								10.5									41.7		10.5
Business Realignment and Reorganization [Member] | Severance And Other Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions																		151.9		12.7
Amount reflected in pension liability																		(14.0)		0.0
Noncash expenses																		0.0
Cash expenditures																		(113.5)		(2.2)
Currency translation adjustment																		(0.4)		0.0
Accrued Balance	34.5								10.5									34.5		10.5
Business Realignment and Reorganization [Member] | Asset Actions [Member]
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions																		55.8		0.0
Amount reflected in pension liability																		0.0		0.0
Noncash expenses																		(47.4)
Cash expenditures																		(1.2)		0.0
Currency translation adjustment																		0.0		0.0
Accrued Balance	7.2								0.0									7.2		0.0
Plan 2013 [Member]
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions																	$ 231.6					231.6
Amount reflected in pension liability																						(6.9)
Noncash expenses																						(100.4)
Cash expenditures																		(9.8)		(52.5)		(61.5)
Currency translation adjustment																		(0.3)		(0.6)		0.4
Accrued Balance	0.0								10.1								63.2	0.0		10.1		63.2
Plan 2013 [Member] | Severance And Other Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions																						71.9
Amount reflected in pension liability																						(6.9)
Noncash expenses																						0.0
Cash expenditures																		(9.8)		(51.7)		(3.0)
Currency translation adjustment																		(0.3)		(0.6)		0.4
Accrued Balance	0.0								10.1								62.4	0.0		10.1		62.4
Plan 2013 [Member] | Asset Actions [Member]
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions																						100.4
Amount reflected in pension liability																						0.0
Noncash expenses																						(100.4)
Cash expenditures																		0.0		0.0		0.0
Currency translation adjustment																		0.0		0.0		0.0
Accrued Balance	0.0								0.0								0.0	0.0		0.0		0.0
Plan 2013 [Member] | Contract Actions [Member]
Restructuring Cost and Reserve [Line Items]
Business restructuring and cost reduction actions																						59.3
Amount reflected in pension liability																						0.0
Noncash expenses																						0.0
Cash expenditures																		0.0		(0.8)		(58.5)
Currency translation adjustment																		0.0		0.0		0.0
Accrued Balance	$ 0.0								$ 0.0								$ 0.8	$ 0.0		$ 0.0		$ 0.8

[1] For additional information, see Note 5, Business Restructuring and Cost Reduction Actions.