Revenue from contracts with customers - disaggregation of revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of Revenue [Line Items]
Revenues	$ 1,216.2	$ 1,133.9	$ 2,401.6	$ 2,207.9
Reportable segments
Disaggregation of Revenue [Line Items]
Revenues	1,216.2	1,133.9	2,401.6	2,207.9
Reportable segments | Cash and valuables management
Disaggregation of Revenue [Line Items]
Revenues	963.6	952.8	1,912.5	1,869.2
Reportable segments | DRS and AMS
Disaggregation of Revenue [Line Items]
Revenues	252.6	181.1	489.1	338.7
Reportable segments | North America
Disaggregation of Revenue [Line Items]
Revenues	397.4	401.6	799.3	770.4
Reportable segments | North America | Cash and valuables management
Disaggregation of Revenue [Line Items]
Revenues	303.0	302.0	611.0	587.0
Reportable segments | North America | DRS and AMS
Disaggregation of Revenue [Line Items]
Revenues	94.4	99.6	188.3	183.4
Reportable segments | Latin America
Disaggregation of Revenue [Line Items]
Revenues	333.9	306.3	649.4	597.6
Reportable segments | Latin America | Cash and valuables management
Disaggregation of Revenue [Line Items]
Revenues	289.0	276.3	563.3	540.5
Reportable segments | Latin America | DRS and AMS
Disaggregation of Revenue [Line Items]
Revenues	44.9	30.0	86.1	57.1
Reportable segments | Europe
Disaggregation of Revenue [Line Items]
Revenues	285.9	226.7	554.6	448.8
Reportable segments | Europe | Cash and valuables management
Disaggregation of Revenue [Line Items]
Revenues	186.7	185.5	366.8	371.1
Reportable segments | Europe | DRS and AMS
Disaggregation of Revenue [Line Items]
Revenues	99.2	41.2	187.8	77.7
Reportable segments | Rest of World
Disaggregation of Revenue [Line Items]
Revenues	199.0	199.3	398.3	391.1
Reportable segments | Rest of World | Cash and valuables management
Disaggregation of Revenue [Line Items]
Revenues	184.9	189.0	371.4	370.6
Reportable segments | Rest of World | DRS and AMS
Disaggregation of Revenue [Line Items]
Revenues	$ 14.1	$ 10.3	$ 26.9	$ 20.5