Income Taxes - Valuation Allowances (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation Allowances [Roll Forward]
Beginning of year				$ 47.4				$ 43.9	$ 47.4	$ 43.9	$ 45.9
Expiring tax credits									(1.8)	(0.8)	(0.3)
Acquisitions and dispositions									(32.7)	(0.9)	0.3
Changes in judgment about deferred tax assets									(0.2)	(1.0)	(8.2)
Valuation and Qualifying Accounts Disclosure [Line Items]
Amounts attributable to Brink's Income (loss) from Continuing operations	26.0	29.8	13.2	2.9	34.0	21.1	33.6	22.5	71.9	111.2	100.3
Income (loss) from discontinued operations	14.9	(6.0)	(4.5)	(19.5)	(6.1)	(7.6)	(3.1)	(5.5)	(15.1)	(22.3)	(25.8)
Other comprehensive income (loss), net of tax									154.6	14.0	(179.6)
Foreign currency exchange effects									1.0	0.8	(1.4)
End of year	32.4				47.4				32.4	47.4	43.9
Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Amounts attributable to Brink's Income (loss) from Continuing operations									6.2	3.4	7.6
Income (loss) from discontinued operations									12.5	1.9	0
Other comprehensive income (loss), net of tax									$ 0	$ 0.1	$ 0