Revenue Recognition - Disaggregation of Revenue by Operating Segment and Major Types of Products or Services (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Sales	$ 1,665.1	$ 1,698.7	$ 4,964.6	$ 4,936.5
Products
Disaggregation of Revenue [Line Items]
Sales	1,105.2		3,343.3
Solutions & Services
Disaggregation of Revenue [Line Items]
Sales	559.9		1,621.3
Architecture & Software
Disaggregation of Revenue [Line Items]
Sales	747.9		2,240.7
Architecture & Software | Products
Disaggregation of Revenue [Line Items]
Sales	747.9		2,240.7
Architecture & Software | Solutions & Services
Disaggregation of Revenue [Line Items]
Sales	0.0		0.0
Control Products & Solutions
Disaggregation of Revenue [Line Items]
Sales	917.2		2,723.9
Control Products & Solutions | Products
Disaggregation of Revenue [Line Items]
Sales	357.3		1,102.6
Control Products & Solutions | Solutions & Services
Disaggregation of Revenue [Line Items]
Sales	$ 559.9		$ 1,621.3