Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Revenues		$ 4,200.2	$ 3,690.9	$ 3,683.2
Costs and expenses:
Cost of revenues		3,235.8	2,877.3	2,832.1
Selling, general and administrative expenses		629.7	584.5	604.9
Total costs and expenses		3,865.5	3,461.8	3,437.0
Other operating income (expense)		20.0	(15.6)	(9.4)
Operating profit		354.7	213.5	236.8
Interest expense		(112.2)	(96.5)	(90.6)
Interest and other nonoperating income (expense)		(7.0)	(37.7)	(52.7)
Income from continuing operations before tax		235.5	79.3	93.5
Provision for income taxes		120.3	56.6	61.0
Income from continuing operations		115.2	22.7	32.5
Income (loss) from discontinued operations, net of tax		2.1	(0.8)	0.7
Net income		117.3	21.9	33.2
Less net income attributable to noncontrolling interests		12.1	5.9	4.2
Net income (loss) attributable to Brink’s		105.2	16.0	29.0
Amounts attributable to Brink’s:
Continuing operations		103.1	16.8	28.3
Discontinued operations		2.1	(0.8)	0.7
Net income (loss) attributable to Brink’s		$ 105.2	$ 16.0	$ 29.0
Basic:
Continuing operations (in dollars per share)	[1]	$ 2.08	$ 0.33	$ 0.56
Discontinued operations (in dollars per share)	[1]	0.04	(0.02)	0.01
Net income (loss) (in dollars per share)	[1]	2.12	0.32	0.58
Diluted:
Continuing operations (in dollars per share)	[1]	2.06	0.33	0.55
Discontinued operations (in dollars per share)	[1]	0.04	(0.02)	0.01
Net income (loss) (in dollars per share)	[1]	$ 2.10	$ 0.31	$ 0.57
Weighted-average shares
Basic (shares)		49.5	50.4	50.2
Diluted (shares)		50.1	50.8	51.1

[1] Amounts may not add due to rounding.