Shareowners' Equity (Details 2) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes									$ 1,127.5	$ 1,134.2	$ 980.9
Income tax provision									(299.9)	(307.4)	(224.6)
Net income	$ 201.3	$ 206.1	$ 206.0	$ 214.2	$ 248.7	$ 199.7	$ 180.3	$ 198.1	827.6	826.8	756.3
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income									33.9	60.7	83.2
Pension and other postretirement benefit plan adjustments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of prior service credit									(17.2)	(12.9)	(13.2)
Amortization of net actuarial loss									123.2	102.6	149.0
Pension and other postretirement benefit plan adjustments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes									106.0	89.7	135.8
Income tax provision									(36.4)	(31.4)	(48.5)
Net income									69.6	58.3	87.3
Net unrealized gains (losses) on cash flow hedges, net of tax [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income before income taxes									(36.2)	1.6	(6.5)
Income tax provision									0.5	0.8	2.4
Net income									(35.7)	2.4	(4.1)
Foreign Exchange Forward [Member] | Sales [Member] | Net unrealized gains (losses) on cash flow hedges, net of tax [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive income, net of tax									8.4	2.3	(1.6)
Foreign Exchange Forward [Member] | Cost of sales [Member] | Net unrealized gains (losses) on cash flow hedges, net of tax [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from accumulated other comprehensive income, net of tax									$ (44.6)	$ (0.7)	$ (4.9)