The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Revenue Recognition - Dual Reporting - Condensed Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Sales
Sales	$ 1,730.2	$ 1,665.1	$ 1,657.2	$ 1,642.3	$ 1,729.5	$ 1,698.7	$ 1,651.2	$ 1,586.6	$ 6,694.8	$ 6,666.0	$ 6,311.3
Cost of sales
Cost of sales									(3,794.7)	(3,781.1)	(3,643.4)
Income tax provision									(205.2)	(795.3)	(211.7)
Impact of Adoption \| Accounting Standards Update 2014-09
Cost of sales
Income tax provision									(0.5)
Balances without adoption of ASC 606
Cost of sales
Income tax provision									(205.7)
Products and solutions
Sales
Sales									5,938.5	5,930.5	5,628.9
Cost of sales
Cost of sales									(3,313.6)	(3,327.5)	(3,216.2)
Products and solutions \| Impact of Adoption \| Accounting Standards Update 2014-09
Sales
Sales									7.1
Cost of sales
Cost of sales									(8.3)
Products and solutions \| Balances without adoption of ASC 606
Sales
Sales									5,945.6
Cost of sales
Cost of sales									(3,321.9)
Services
Sales
Sales									756.3	735.5	682.4
Cost of sales
Cost of sales									(481.1)	$ (453.6)	$ (427.2)
Services \| Impact of Adoption \| Accounting Standards Update 2014-09
Sales
Sales									(16.1)
Cost of sales
Cost of sales									18.6
Services \| Balances without adoption of ASC 606
Sales
Sales									740.2
Cost of sales
Cost of sales									$ (462.5)