Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Revenues		$ 3,347.0	$ 3,020.6	$ 3,061.4
Costs and expenses:
Cost of revenues		2,608.2	2,391.7	2,443.7
Selling, general and administrative expenses		468.2	424.3	451.9
Total costs and expenses		3,076.4	2,816.0	2,895.6
Other operating income (expense)		3.3	(20.1)	(69.4)
Operating profit		273.9	184.5	96.4
Interest expense		(32.2)	(20.4)	(18.9)
Interest and other expense		(60.2)	(39.1)	(36.4)
Income from continuing operations before tax		181.5	125.0	41.1
Provision for income taxes		157.7	78.5	66.5
Income (loss) from continuing operations		23.8	46.5	(25.4)
Loss from discontinued operations, net of tax		(0.2)	(1.7)	(2.8)
Net income (loss)		23.6	44.8	(28.2)
Less net income (loss) attributable to noncontrolling interests		6.9	10.3	(16.3)
Net income (loss) attributable to Brink’s		16.7	34.5	(11.9)
Amounts attributable to Brink’s:
Continuing operations		16.9	36.2	(9.1)
Discontinued operations		(0.2)	(1.7)	(2.8)
Net income (loss) attributable to Brink’s		$ 16.7	$ 34.5	$ (11.9)
Basic:
Continuing operations (in dollars per share)	[1]	$ 0.33	$ 0.72	$ (0.19)
Discontinued operations (in dollars per share)	[1]	(0.01)	(0.03)	(0.06)
Net income (loss) (in dollars per share)	[1]	0.33	0.69	(0.24)
Diluted:
Continuing operations (in dollars per share)	[1]	0.33	0.72	(0.19)
Discontinued operations (in dollars per share)	[1]	(0.01)	(0.03)	(0.06)
Net income (loss) (in dollars per share)	[1]	$ 0.32	$ 0.68	$ (0.24)
Weighted-average shares
Basic (shares)		50.7	50.0	49.3
Diluted (shares)		51.8	50.6	49.3

[1] Amounts may not add due to rounding.