Revenue Recognition - Disaggregation of Revenue by Operating Segment and by Geographic Region (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Sales	$ 1,776.1	$ 1,681.3	$ 3,341.4	$ 3,365.8
North America
Disaggregation of Revenue [Line Items]
Sales	1,065.7	1,022.1	1,978.0	2,029.0
Europe, Middle East and Africa (EMEA)
Disaggregation of Revenue [Line Items]
Sales	354.8	333.6	675.5	643.7
Asia Pacific
Disaggregation of Revenue [Line Items]
Sales	246.9	200.8	468.8	430.4
Latin America
Disaggregation of Revenue [Line Items]
Sales	108.7	124.8	219.1	262.7
Intelligent Devices
Disaggregation of Revenue [Line Items]
Sales	850.2	785.0	1,571.9	1,561.7
Intelligent Devices | North America
Disaggregation of Revenue [Line Items]
Sales	538.9	500.1	988.2	986.8
Intelligent Devices | Europe, Middle East and Africa (EMEA)
Disaggregation of Revenue [Line Items]
Sales	152.0	138.5	282.3	266.3
Intelligent Devices | Asia Pacific
Disaggregation of Revenue [Line Items]
Sales	106.7	89.6	198.5	187.0
Intelligent Devices | Latin America
Disaggregation of Revenue [Line Items]
Sales	52.6	56.8	102.9	121.6
Software & Control
Disaggregation of Revenue [Line Items]
Sales	502.3	448.2	943.3	900.7
Software & Control | North America
Disaggregation of Revenue [Line Items]
Sales	309.2	283.5	575.6	563.3
Software & Control | Europe, Middle East and Africa (EMEA)
Disaggregation of Revenue [Line Items]
Sales	98.1	76.8	182.9	150.9
Software & Control | Asia Pacific
Disaggregation of Revenue [Line Items]
Sales	67.0	58.5	129.6	125.5
Software & Control | Latin America
Disaggregation of Revenue [Line Items]
Sales	28.0	29.4	55.2	61.0
Lifecycle Services
Disaggregation of Revenue [Line Items]
Sales	423.6	448.1	826.2	903.4
Lifecycle Services | North America
Disaggregation of Revenue [Line Items]
Sales	217.6	238.5	414.2	478.9
Lifecycle Services | Europe, Middle East and Africa (EMEA)
Disaggregation of Revenue [Line Items]
Sales	104.7	118.3	210.3	226.5
Lifecycle Services | Asia Pacific
Disaggregation of Revenue [Line Items]
Sales	73.2	52.7	140.7	117.9
Lifecycle Services | Latin America
Disaggregation of Revenue [Line Items]
Sales	$ 28.1	$ 38.6	$ 61.0	$ 80.1