Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 2.8	$ 14.5
Benefit plan adjustments:
Benefit plan actuarial gains	18.6	11.3
Benefit plan prior service costs	(1.1)	(1.3)
Total benefit plan adjustments	17.5	10.0
Foreign currency translation adjustments	(120.3)	0.6
Losses on cash flow hedges	(14.7)	(7.9)
Other comprehensive income (loss) before tax	(117.5)	2.7
Provision (benefit) for income taxes	(0.1)	0.5
Other comprehensive income (loss)	(117.4)	2.2
Comprehensive income (loss)	(114.6)	16.7
Less comprehensive income attributable to noncontrolling interests	0.6	1.1
Comprehensive income (loss) attributable to Brink's	$ (115.2)	$ 15.6