Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Net sales	$ 1,228.9	$ 1,162.0	$ 3,587.6	$ 3,065.0
Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Net sales	932.8	865.2	2,721.0	2,247.8
Transferred over Time
Disaggregation of Revenue [Line Items]
Net sales	296.1	296.8	866.6	817.2
Critical infrastructure & solutions
Disaggregation of Revenue [Line Items]
Net sales	706.3	656.5	2,061.3	1,662.5
Critical infrastructure & solutions | Restatement Adjustment
Disaggregation of Revenue [Line Items]
Net sales		5.8		15.6
Services & spares
Disaggregation of Revenue [Line Items]
Net sales	365.4	341.0	1,049.1	959.3
Services & spares | Restatement Adjustment
Disaggregation of Revenue [Line Items]
Net sales		0.9		5.6
Integrated rack solutions
Disaggregation of Revenue [Line Items]
Net sales	157.2	164.5	477.2	443.2
Integrated rack solutions | Restatement Adjustment
Disaggregation of Revenue [Line Items]
Net sales		(6.7)		(21.3)
Americas
Disaggregation of Revenue [Line Items]
Net sales	537.2	532.0	1,603.6	1,483.3
Americas | Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Net sales	363.5	376.7	1,111.1	1,022.3
Americas | Transferred over Time
Disaggregation of Revenue [Line Items]
Net sales	173.7	155.3	492.5	461.0
Americas | Critical infrastructure & solutions
Disaggregation of Revenue [Line Items]
Net sales	291.9	278.7	877.2	769.9
Americas | Services & spares
Disaggregation of Revenue [Line Items]
Net sales	180.2	168.3	513.4	491.0
Americas | Integrated rack solutions
Disaggregation of Revenue [Line Items]
Net sales	65.1	85.0	213.0	222.4
Asia Pacific
Disaggregation of Revenue [Line Items]
Net sales	394.6	379.6	1,149.9	926.4
Asia Pacific | Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Net sales	316.0	302.6	913.3	720.4
Asia Pacific | Transferred over Time
Disaggregation of Revenue [Line Items]
Net sales	78.6	77.0	236.6	206.0
Asia Pacific | Critical infrastructure & solutions
Disaggregation of Revenue [Line Items]
Net sales	234.0	239.6	690.0	549.6
Asia Pacific | Services & spares
Disaggregation of Revenue [Line Items]
Net sales	104.4	94.8	305.8	260.5
Asia Pacific | Integrated rack solutions
Disaggregation of Revenue [Line Items]
Net sales	56.2	45.2	154.1	116.3
Europe, Middle East, & Africa
Disaggregation of Revenue [Line Items]
Net sales	297.1	250.4	834.1	655.3
Europe, Middle East, & Africa | Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Net sales	253.3	185.9	696.6	505.1
Europe, Middle East, & Africa | Transferred over Time
Disaggregation of Revenue [Line Items]
Net sales	43.8	64.5	137.5	150.2
Europe, Middle East, & Africa | Critical infrastructure & solutions
Disaggregation of Revenue [Line Items]
Net sales	180.4	138.2	494.1	343.0
Europe, Middle East, & Africa | Services & spares
Disaggregation of Revenue [Line Items]
Net sales	80.8	77.9	229.9	207.8
Europe, Middle East, & Africa | Integrated rack solutions
Disaggregation of Revenue [Line Items]
Net sales	$ 35.9	$ 34.3	$ 110.1	$ 104.5