Income Taxes - Valuation Allowances (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Valuation and Qualifying Accounts Disclosure [Line Items]    
Amounts attributable to Brink's Income (loss) from Continuing operations $ (0.6) $ (59.0)
Income (loss) from discontinued operations (2.4) 0.5
Other comprehensive income (loss), net of tax $ (43.2) $ 2.8