Debt (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Short-term borrowings	$ 151.7	$ 47.2
Long-term Debt Types [Abstract]
Financing leases	233.8
Total long-term debt	3,379.6	3,355.6
Total Debt	3,531.3	3,402.8
Long Term Debt By Current And Noncurrent [Abstract]
Current liabilities	268.8	129.6
Noncurrent liabilities	3,262.5	3,273.2
Interest Rate And Other Disclosures [Abstract]
Long-term revolving credit facilities: Borrowings	9,265.7	7,058.7	$ 3,385.5
Long-term revolving credit facilities: Repayments	(9,273.8)	(6,832.7)	$ (2,836.8)
Brink's Capital credit facility
Interest Rate And Other Disclosures [Abstract]
Long-term revolving credit facilities: Borrowings	7,110.5
Long-term revolving credit facilities: Repayments	(7,008.1)
Term Loan A | Senior Secured Credit Facility - Amended III
Long-term Debt Types [Abstract]
Long-term Debt	$ 1,343.5	$ 1,377.4
Interest Rate And Other Disclosures [Abstract]
Effective interest rate	7.00%	5.70%
Debt issue cost	$ 4.0	$ 5.1
Senior unsecured notes | Six hundred million senior unsecured notes
Long-term Debt Types [Abstract]
Long-term Debt	$ 994.4	$ 992.1
Interest Rate And Other Disclosures [Abstract]
Effective interest rate	4.60%	4.60%
Debt issue cost	$ 5.6	$ 7.9
Senior unsecured notes | Four hundred million senior unsecured notes
Interest Rate And Other Disclosures [Abstract]
Effective interest rate	5.50%	5.50%
Revolving Credit Facility
Long-term Debt Types [Abstract]
Debt	$ 542.1	$ 646.9
Interest Rate And Other Disclosures [Abstract]
Average interest rate	6.30%	5.50%
Other Non-US Dollar-denominated Facilities
Long-term Debt Types [Abstract]
Debt	$ 265.8	$ 147.0
Interest Rate And Other Disclosures [Abstract]
Average interest rate	5.90%	4.80%
Other Non-US Dollar-denominated Facilities | Brink's Capital credit facility
Long-term Debt Types [Abstract]
Debt	$ 209.3	$ 106.8
Financing leases
Long-term Debt Types [Abstract]
Financing leases	$ 233.8	$ 192.2
Interest Rate And Other Disclosures [Abstract]
Average interest rate	6.20%	5.50%
Other
Debt Instrument [Line Items]
Short-term borrowings	$ 151.7	$ 47.2
Interest Rate And Other Disclosures [Abstract]
Short-term borrowings interest rate	6.50%	4.30%