RETIREMENT AND POSTRETIREMENT BENEFIT PLANS (Schedule of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Settlement charge			$ 9.6
Special termination benefits	$ 3.2
Master Defined Benefit Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		5.0	5.4	5.0
Interest cost		10.9	14.6	14.4
Expected return on plan assets		(13.0)	(16.7)	(16.7)
Amortization of unrecognized prior service cost, net		0.3	0.6	0.6
Amortization of net loss		4.5	5.2	3.2
Net periodic benefit cost		7.7	9.1	6.5
Settlement charge			9.6
Special termination benefits	$ 2.4			2.4
Net pension expense		$ 7.7	$ 18.7	$ 8.9