Condensed Consolidated Statement of Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning balance at Dec. 31, 2021	$ 252.6	$ 47.4	$ 670.6	$ 312.9	$ (907.9)	$ 129.6
Beginning balance, Shares at Dec. 31, 2021		47.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	74.2			71.3		2.9
Other comprehensive income (loss)	49.4				50.9	(1.5)
Dividends to:
Brink’s common shareholders	(9.5)			(9.5)
Noncontrolling interests	(1.2)					(1.2)
Stock options and awards
Compensation expense	7.1		7.1
Other share-based benefit transactions	(2.8)	$ 0.2	(3.0)
Other share-based benefit transactions, shares		0.2
Ending balance at Mar. 31, 2022	369.8	$ 47.6	674.7	374.7	(857.0)	129.8
Ending balance, Shares at Mar. 31, 2022		47.6
Beginning balance at Dec. 31, 2021	252.6	$ 47.4	670.6	312.9	(907.9)	129.6
Beginning balance, Shares at Dec. 31, 2021		47.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	112.3
Other comprehensive income (loss)	9.8				16.3
Ending balance at Jun. 30, 2022	366.7	$ 47.2	676.1	408.8	(891.6)	126.2
Ending balance, Shares at Jun. 30, 2022		47.2
Beginning balance at Mar. 31, 2022	369.8	$ 47.6	674.7	374.7	(857.0)	129.8
Beginning balance, Shares at Mar. 31, 2022		47.6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	38.1			35.1		3.0
Other comprehensive income (loss)	(39.6)				(34.6)	(5.0)
Shares repurchased	0.0	$ (0.5)	(8.0)	8.5
Stock Repurchased During Period, Shares		(0.5)
Dividends to:
Brink’s common shareholders	(9.4)			(9.4)
Noncontrolling interests	(1.6)					(1.6)
Stock options and awards
Compensation expense	14.9		14.9
Other share-based benefit transactions	(5.5)	$ 0.1	(5.5)	(0.1)
Other share-based benefit transactions, shares		0.1
Ending balance at Jun. 30, 2022	366.7	$ 47.2	676.1	408.8	(891.6)	126.2
Ending balance, Shares at Jun. 30, 2022		47.2
Beginning balance at Dec. 31, 2022	570.2	$ 46.3	684.1	417.2	(700.5)	123.1
Beginning balance, Shares at Dec. 31, 2022		46.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	18.3			15.0		3.3
Other comprehensive income (loss)	36.0				35.8	0.2
Shares repurchased	(16.0)	$ (0.2)	(3.8)	(12.0)
Stock Repurchased During Period, Shares		(0.2)
Dividends to:
Brink’s common shareholders	(9.3)			(9.3)
Noncontrolling interests	(0.4)					(0.4)
Stock options and awards
Compensation expense	10.9		10.9
Other share-based benefit transactions	(4.7)	$ 0.3	(4.8)	(0.2)
Other share-based benefit transactions, shares		0.3
Ending balance at Mar. 31, 2023	605.0	$ 46.4	686.4	410.7	(664.7)	126.2
Ending balance, Shares at Mar. 31, 2023		46.4
Beginning balance at Dec. 31, 2022	570.2	$ 46.3	684.1	417.2	(700.5)	123.1
Beginning balance, Shares at Dec. 31, 2022		46.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	53.4
Other comprehensive income (loss)	66.3				69.1
Ending balance at Jun. 30, 2023	664.2	$ 46.4	694.9	431.4	(631.4)	122.9
Ending balance, Shares at Jun. 30, 2023		46.4
Beginning balance at Mar. 31, 2023	605.0	$ 46.4	686.4	410.7	(664.7)	126.2
Beginning balance, Shares at Mar. 31, 2023		46.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	35.1			32.1		3.0
Other comprehensive income (loss)	30.3				33.3	(3.0)
Shares repurchased	(1.5)	$ (0.1)	(0.3)	(1.1)
Stock Repurchased During Period, Shares		(0.1)
Dividends to:
Brink’s common shareholders	(10.2)			(10.2)
Noncontrolling interests	(2.4)					(2.4)
Stock options and awards
Compensation expense	8.3		8.3
Other share-based benefit transactions	0.2	$ 0.1	0.2	(0.1)
Other share-based benefit transactions, shares		0.1
Acquisitions of noncontrolling interests	(0.6)		0.3			(0.9)
Ending balance at Jun. 30, 2023	$ 664.2	$ 46.4	$ 694.9	$ 431.4	$ (631.4)	$ 122.9
Ending balance, Shares at Jun. 30, 2023		46.4