Inventories (Schedule of Inventory) (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2015
Sep. 30, 2014
Inventories [Abstract]    
Finished goods $ 509.2 $ 493.9
Work in process 36.3 34.1
Raw materials, supplies and other 259.4 283.4
Total FIFO value 804.9 811.4
Less: Excess of FIFO cost over LIFO cost (111.6) (105.4)
Inventories $ 693.3 $ 706.0