Selected Quarterly Financial Data (unaudited) (Details) - USD ($)	3 Months Ended								6 Months Ended	12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Quarterly Financial Data [Abstract]
Revenues	$ 907,700,000	$ 852,400,000	$ 849,700,000	$ 879,100,000	$ 903,200,000	$ 849,500,000	$ 805,900,000	$ 788,400,000		$ 3,488,900,000		$ 3,347,000,000		$ 3,020,600,000
Operating Profit	81,200,000	67,000,000	61,700,000	64,800,000	88,300,000	66,400,000	48,300,000	70,900,000		274,700,000		273,900,000		184,500,000
Amounts attributable to Brink’s:
Continuing operations	34,900,000	17,500,000	(107,800,000)	22,100,000	(52,000,000)	19,900,000	14,300,000	34,700,000		(33,300,000)		16,900,000		36,200,000
Discontinued operations	0	(100,000)	(100,000)	200,000	(100,000)	0	(100,000)	0		0		(200,000)		(1,700,000)
Net income (loss) attributable to Brink’s	34,900,000	17,400,000	(107,900,000)	22,300,000	(52,100,000)	19,900,000	14,200,000	34,700,000		(33,300,000)		16,700,000		34,500,000
Depreciation and amortization	42,800,000	41,600,000	39,100,000	38,800,000	40,200,000	37,900,000	34,600,000	33,900,000		162,300,000		146,600,000		131,600,000
Capital expenditures	$ 51,100,000	$ 30,700,000	$ 36,600,000	$ 36,700,000	$ 57,100,000	$ 46,300,000	$ 43,300,000	$ 27,800,000		$ 155,100,000		$ 174,500,000		$ 112,200,000
Basic
Continuing operations (in dollars per share)	$ 0.69	$ 0.34	$ (2.11)	$ 0.43	$ (1.02)	$ 0.39	$ 0.28	$ 0.69		$ (0.65)	[1]	$ 0.33	[1]	$ 0.72	[1]
Discontinued operations (in dollars per share)	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00		0.00	[1]	(0.01)	[1]	(0.03)	[1]
Net income (loss) (in dollars per share)	0.69	0.34	(2.11)	0.44	(1.03)	0.39	0.28	0.69		(0.65)	[1]	0.33	[1]	0.69	[1]
Diluted
Continuing operations (in dollars per share)	0.68	0.34	(2.11)	0.42	(1.02)	0.38	0.28	0.67		(0.65)	[1]	0.33	[1]	0.72	[1]
Discontinued operations (in dollars per share)	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00		0.00	[1]	(0.01)	[1]	(0.03)	[1]
Net income (loss) (in dollars per share)	$ 0.68	$ 0.34	$ (2.11)	$ 0.43	$ (1.03)	$ 0.38	$ 0.28	$ 0.67		$ (0.65)	[1]	$ 0.32	[1]	$ 0.68	[1]
Effect of Fourth Quarter Events [Line Items]
Loss on deconsolidation of Venezuela operations										$ (126,700,000)		$ 0		$ 0
Foreign currency transaction losses										(15,500,000)		(7,600,000)		0
Gain on sale of business										11,200,000		0		0
Prepayment penalties										0		8,300,000		0
Loss Due to Gold Theft					$ 11,100,000
Gain on sale of property										4,000,000		9,200,000		(1,300,000)
Tax Reform Act Tax Expense Charge					92,000,000
ARGENTINA
Quarterly Financial Data [Abstract]
Revenues										247,200,000		250,300,000		156,400,000
Venezuela
Quarterly Financial Data [Abstract]
Revenues										51,400,000		154,100,000		109,400,000
Mexico
Quarterly Financial Data [Abstract]
Revenues										365,300,000		327,200,000		296,300,000
Effect of Fourth Quarter Events [Line Items]
Gain on sale of property					$ 7,800,000					3,000,000		8,400,000
Argentina, Pesos | ARGENTINA
Effect of Fourth Quarter Events [Line Items]
Foreign currency transaction losses			$ 12,600,000
Currency remeasurement gain (loss)		$ (8,100,000)								(6,200,000)
Venezuelan bolívar fuerte | Venezuela
Effect of Fourth Quarter Events [Line Items]
Loss on deconsolidation of Venezuela operations			$ 126,700,000
Currency remeasurement gain (loss)							$ (8,100,000)		$ 2,200,000			$ (9,100,000)		$ (4,800,000)
Private Placement Notes
Effect of Fourth Quarter Events [Line Items]
Prepayment penalties						$ 6,500,000
French airport security services company
Effect of Fourth Quarter Events [Line Items]
Gain on sale of business										$ 11,200,000

[1] Amounts may not add due to rounding.