Business Restructuring and Cost Reduction Actions (Carrying Amount of Accrual) (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 6 Months Ended 3 Months Ended 12 Months Ended 3 Months Ended 12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2015
Mar. 31, 2014
Sep. 30, 2014
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2013
Restructuring Cost and Reserve [Line Items]                
Business restructuring and cost reduction actions $ 55.4 $ 0 $ 87.8 $ 0        
Business Realignment and Reorganization [Member]                
Restructuring Cost and Reserve [Line Items]                
Business restructuring and cost reduction actions 55.4   87.8   12.7      
Business Realignment and Reorganization [Member] | Severance And Other Benefits [Member]                
Restructuring Cost and Reserve [Line Items]                
Business restructuring and cost reduction actions     87.8     12.7    
Amount reflected in pension liability     (8.8)          
Cash expenditures     (57.4)     (2.2)    
Currency translation adjustment     (1.1)          
Accrued Balance 31.0   31.0   10.5 10.5    
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 10.1 63.2 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
Cash expenditures     (9.8)     (51.7)   (3.0)
Currency translation adjustment     (0.3)     (0.6)   0.4
Accrued Balance 0   0   10.1 10.1 62.4 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
Noncash expenses               (100.4)
Cash expenditures           0   0
Currency translation adjustment           0   0
Accrued Balance         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
Noncash expenses               0
Cash expenditures           (0.8)   (58.5)
Currency translation adjustment           0   0
Accrued Balance         $ 0 $ 0 $ 0.8 $ 0.8