Revenue Recognition - Disaggregation of Revenue by Operating Segment and Major Types of Products or Services (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Sales	$ 1,684.5	$ 1,642.3
Products
Disaggregation of Revenue [Line Items]
Sales	1,140.2	1,126.0
Solutions & Services
Disaggregation of Revenue [Line Items]
Sales	544.3	516.3
Architecture & Software
Disaggregation of Revenue [Line Items]
Sales	751.6	753.1
Architecture & Software | Products
Disaggregation of Revenue [Line Items]
Sales	751.6	753.1
Architecture & Software | Solutions & Services
Disaggregation of Revenue [Line Items]
Sales	0.0	0.0
Control Products & Solutions
Disaggregation of Revenue [Line Items]
Sales	932.9	889.2
Control Products & Solutions | Products
Disaggregation of Revenue [Line Items]
Sales	388.6	372.9
Control Products & Solutions | Solutions & Services
Disaggregation of Revenue [Line Items]
Sales	$ 544.3	$ 516.3