Basis of presentation (Details)		3 Months Ended			9 Months Ended		12 Months Ended
	Nov. 30, 2015	Sep. 30, 2016 USD ($) Country Region ARS / $ VEF / $	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Segment Country Region ARS / $ VEF / $	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) VEF / $	Mar. 31, 2016 VEF / $	Dec. 31, 2014 USD ($) VEF / $	Mar. 31, 2014 VEF / $
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments | Segment					9
Number of countries in which the entity operates, within the five largest markets | Country		5			5
Number of regions in which the entity operates, within global markets | Region		3			3
Cash and cash equivalents		$ 191,500,000	$ 176,100,000		$ 191,500,000	$ 176,100,000	$ 181,900,000		$ 176,200,000
Accumulated other comprehensive losses related to Venezuela		859,200,000			859,200,000		891,900,000
Venezuela impairment charge			800,000	$ 34,500,000	0	35,300,000
Revenues		755,800,000	759,200,000		2,217,100,000	2,295,600,000
Restricted cash		46,800,000			46,800,000		16,400,000
Accrued liabilities		382,200,000			382,200,000		401,200,000
Restricted cash held for customers		33,300,000			33,300,000		12,900,000
Short-term borrowings		80,500,000			80,500,000		32,600,000
Current maturities of long-term debt		$ 31,600,000			31,600,000		39,800,000
Net cash provided (used) by operating activities					57,000,000	90,800,000
Net cash provided by financing activities					26,600,000	(400,000)
Venezuela
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Official exchange rate | VEF / $									51
Foreign currency transaction losses						18,100,000
Income (loss) attributable to noncontrolling interest					$ 2,700,000	(5,700,000)
Remeasurement rate | VEF / $		659			659			273
Rate decrease percent		59.00%			59.00%
Accumulated other comprehensive losses related to Venezuela		$ 112,500,000			$ 112,500,000
Carrying value of long-lived assets		$ 9,700,000			9,700,000
Ireland
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues							$ 20,000,000
Severance costs					4,800,000
Property impairment charge					2,000,000
Losses associated with exiting operations					$ 5,300,000
Argentina
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Official exchange rate | ARS / $		15.4			15.4
Minimum | Venezuela
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Official exchange rate | VEF / $							170			49
Maximum | Venezuela
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Official exchange rate | VEF / $							200			52
Venezuelan bolívar fuerte | Venezuela
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Amount approved to be obtained									$ 1,200,000
Net remeasurement loss					$ 4,700,000
Nonmonetary assets		$ 16,700,000			16,700,000		$ 13,500,000
Investment in Venezuela operations		20,600,000			20,600,000		26,000,000
Net monetary assets		2,400,000			2,400,000		9,500,000
Cash and cash equivalents		5,800,000			5,800,000		6,200,000
Accumulated other comprehensive losses related to Venezuela		112,500,000			112,500,000		113,000,000
Argentine pesos | Argentina
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents		11,200,000			11,200,000
Losses from converting local pesos into U.S. dollars			$ 2,300,000		100,000	$ 2,300,000.0
Argentine pesos | Minimum | Argentina
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percent less favorable	30.00%
Argentine pesos | Maximum | Argentina
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percent less favorable	40.00%
Venezuela Investment | Venezuela
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net payables to other Brink's affiliates		$ 9,300,000			9,300,000		18,700,000
Adjustment for Error Correction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents							(16,400,000)
Restricted cash held for customers							12,900,000
Short-term borrowings							3,500,000
Net cash provided (used) by operating activities					195,900,000		208,800,000
Net cash provided by financing activities					52,500,000		49,000,000
Restatement Adjustment | Adjustment for Error Correction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash							16,400,000
Accrued liabilities							(12,900,000)
Current maturities of long-term debt							$ 3,500,000
Contract Terminations | Ireland
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restructuring lease agreements					$ 500,000