Revenue Recognition - Dual Reporting - Consolidated Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2018	Oct. 01, 2018	Sep. 30, 2018
Current assets:
Receivables	$ 1,188.7	$ 1,194.6	$ 1,190.1
Other current assets	168.5	167.0	149.3
Deferred income taxes	196.4	180.8	179.6
Other assets	109.1	107.6	96.2
Current liabilities:
Contract liabilities	293.0	268.6	249.9
Customer returns, rebates and incentives	196.2	211.0	206.6
Other current liabilities	295.3	232.2	226.6
Shareowners’ equity:
Retained earnings	6,167.6	6,204.2	6,198.1
Accumulated other comprehensive loss	(976.9)		(941.9)
Impact of Adoption | Accounting Standards Update 2014-09
Current assets:
Receivables	(3.0)	4.5
Other current assets	(16.4)	17.7
Deferred income taxes	(1.2)	1.2
Other assets	(10.9)	11.4
Current liabilities:
Contract liabilities	(20.4)	18.7
Customer returns, rebates and incentives	(3.0)	4.4
Other current liabilities	(4.5)	$ 5.6
Shareowners’ equity:
Retained earnings	(3.8)
Accumulated other comprehensive loss	0.2
Balances without adoption of ASC 606
Current assets:
Receivables	1,185.7		1,190.1
Other current assets	152.1		149.3
Deferred income taxes	195.2		179.6
Other assets	98.2		96.2
Current liabilities:
Contract liabilities	272.6		249.9
Customer returns, rebates and incentives	193.2		206.6
Other current liabilities	290.8		226.6
Shareowners’ equity:
Retained earnings	6,163.8		$ 6,198.1
Accumulated other comprehensive loss	$ (976.7)