RETIREMENT AND POSTRETIREMENT BENEFIT PLANS (Schedule of Fair Value Measurements of Plan Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Fair Value Measurements of Plan Assets
Plan assets at fair value	$ 267.0	$ 219.1
Master Defined Benefit Retirement Plan [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	267.0	219.1	$ 276.1
Master Defined Benefit Retirement Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	3.7	3.5
Master Defined Benefit Retirement Plan [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	263.3	215.6
Master Defined Benefit Retirement Plan [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | Cash and Cash Equivalents [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	3.7	3.5
Master Defined Benefit Retirement Plan [Member] | Cash and Cash Equivalents [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	3.7	3.5
Master Defined Benefit Retirement Plan [Member] | Cash and Cash Equivalents [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | Cash and Cash Equivalents [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | U.S. Companies Equities [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	59.3	47.1
Master Defined Benefit Retirement Plan [Member] | U.S. Companies Equities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | U.S. Companies Equities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	59.3	47.1
Master Defined Benefit Retirement Plan [Member] | U.S. Companies Equities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | International Companies Equities [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	56.4	44.8
Master Defined Benefit Retirement Plan [Member] | International Companies Equities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | International Companies Equities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	56.4	44.8
Master Defined Benefit Retirement Plan [Member] | International Companies Equities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | Fixed Income Securities [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	147.6	123.7
Master Defined Benefit Retirement Plan [Member] | Fixed Income Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value
Master Defined Benefit Retirement Plan [Member] | Fixed Income Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value	147.6	123.7
Master Defined Benefit Retirement Plan [Member] | Fixed Income Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements of Plan Assets
Plan assets at fair value