Shareowners' Equity (Details 1) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ (1,334.6)	$ (948.0)	$ (817.7)
Other comprehensive (loss) income before reclassifications, net of tax	(262.6)	(420.5)	(191.0)
Amounts reclassified from accumulated other comprehensive loss, net of tax	58.4	33.9	60.7
Other comprehensive loss	(204.2)	(386.6)	(130.3)
Balance at end of period	(1,538.8)	(1,334.6)	(948.0)
Pension and other postretirement benefit plan adjustments [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(1,097.1)	(909.4)	(823.8)
Other comprehensive (loss) income before reclassifications, net of tax	(216.5)	(257.3)	(143.9)
Amounts reclassified from accumulated other comprehensive loss, net of tax	73.8	69.6	58.3
Other comprehensive loss	(142.7)	(187.7)	(85.6)
Balance at end of period	(1,239.8)	(1,097.1)	(909.4)
Accumulated currency translation adjustments, net of tax [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(252.4)	(52.5)	8.8
Other comprehensive (loss) income before reclassifications, net of tax	(42.5)	(199.9)	(61.3)
Amounts reclassified from accumulated other comprehensive loss, net of tax	0.0	0.0	0.0
Other comprehensive loss	(42.5)	(199.9)	(61.3)
Balance at end of period	(294.9)	(252.4)	(52.5)
Net unrealized gains (losses) on cash flow hedges, net of tax [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	14.9	13.9	(2.7)
Other comprehensive (loss) income before reclassifications, net of tax	(3.6)	36.7	14.2
Amounts reclassified from accumulated other comprehensive loss, net of tax	(15.4)	(35.7)	2.4
Other comprehensive loss	(19.0)	1.0	16.6
Balance at end of period	$ (4.1)	$ 14.9	$ 13.9