Accumulated Other Comprehensive Loss (Details 1) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	$ 252.3	$ 284.6	$ 706.2	$ 848.6
Income tax provision	(61.3)	(78.5)	(161.7)	(222.3)
Net income	191.0	206.1	544.5	626.3
Reclassification out of Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	17.4	4.0	42.6	28.3
Pension and other postretirement benefit plan adjustments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of prior service credit	(3.5)	(4.4)	(10.6)	(13.1)
Amortization of net actuarial loss	31.8	30.8	95.3	92.7
Pension and other postretirement benefit plan adjustments [Member] | Reclassification out of Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	28.3	26.4	84.7	79.6
Income tax provision	(9.8)	(9.0)	(29.4)	(27.4)
Net income	18.5	17.4	55.3	52.2
Net unrealized gains (losses) on cash flow hedges [Member] | Reclassification out of Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes	(1.0)	(14.1)	(15.9)	(24.1)
Income tax provision	(0.1)	0.7	3.2	0.2
Net income	(1.1)	(13.4)	(12.7)	(23.9)
Net unrealized gains (losses) on cash flow hedges [Member] | Foreign Exchange Forward [Member] | Sales [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive loss	1.0	2.0	5.1	5.6
Net unrealized gains (losses) on cash flow hedges [Member] | Foreign Exchange Forward [Member] | Cost of sales [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive loss	$ (2.0)	$ (16.1)	$ (21.0)	$ (29.7)