Accumulated Other Comprehensive Income - Reclasses Out Of AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income [Abstract]
Beginning balance - AOCI	$ (792.0)
Other comprehensive income (loss)	(103.4)	$ (181.5)	$ 154.6
Acquisitions of noncontrolling interests	(1.5)		(18.5)
Ending Balance - AOCI	(891.9)	(792.0)
Amounts attributable to Brink's:
Accumulated Other Comprehensive Income [Abstract]
Beginning balance - AOCI	(792.0)	(617.3)	(773.4)
Other comprehensive income (loss) before reclassifications	(138.9)	(234.5)	109.6
Amounts reclassified from accumulated other comprehensive loss	39.3	59.8	46.8
Other comprehensive income (loss)	(99.6)	(174.7)	156.4
Acquisitions of noncontrolling interests	(0.3)		(0.3)
Ending Balance - AOCI	(891.9)	(792.0)	(617.3)
Benefit Plan Adjustments | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Abstract]
Beginning balance - AOCI	(571.7)	(478.0)	(665.1)
Other comprehensive income (loss) before reclassifications	(36.7)	(153.1)	137.8
Amounts reclassified from accumulated other comprehensive loss	37.9	59.4	49.3
Other comprehensive income (loss)	1.2	(93.7)	187.1
Acquisitions of noncontrolling interests	0.0		0.0
Ending Balance - AOCI	(570.5)	(571.7)	(478.0)
Foreign Currency Translation Adjustments | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Abstract]
Beginning balance - AOCI	(222.1)	(141.5)	(109.9)
Other comprehensive income (loss) before reclassifications	(105.9)	(82.2)	(30.9)
Amounts reclassified from accumulated other comprehensive loss	5.7	1.6	(0.4)
Other comprehensive income (loss)	(100.2)	(80.6)	(31.3)
Acquisitions of noncontrolling interests	(0.3)		(0.3)
Ending Balance - AOCI	(322.6)	(222.1)	(141.5)
Unrealized Gains (Losses) on Available-for-Sale Securities | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Abstract]
Beginning balance - AOCI	1.4	1.6	1.6
Other comprehensive income (loss) before reclassifications	0.4	0.1	(0.2)
Amounts reclassified from accumulated other comprehensive loss	(0.7)	(0.3)	0.2
Other comprehensive income (loss)	(0.3)	(0.2)	0.0
Acquisitions of noncontrolling interests	0.0		0.0
Ending Balance - AOCI	1.1	1.4	1.6
Gains (Losses) on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Abstract]
Beginning balance - AOCI	0.4	0.6	0.0
Other comprehensive income (loss) before reclassifications	3.3	0.7	2.9
Amounts reclassified from accumulated other comprehensive loss	(3.6)	(0.9)	(2.3)
Other comprehensive income (loss)	(0.3)	(0.2)	0.6
Acquisitions of noncontrolling interests	0.0		0.0
Ending Balance - AOCI	$ 0.1	$ 0.4	$ 0.6