Consolidated Statement of Equity - USD ($) shares in Millions, $ in Millions		Total	Cumulative Effect, Period of Adoption, Adjustment		Common Stock	Capital in Excess of Par Value	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment		AOCI*	AOCI* Cumulative Effect, Period of Adoption, Adjustment	Noncontrolling Interests
Beginning Balance at Dec. 31, 2019		$ 207.6			$ 50.1	$ 663.3	$ 457.4			$ (979.0)		$ 15.8
Beginning Balance (shares) at Dec. 31, 2019					50.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Tax cuts and jobs act, reclassification from AOCI to retained earnings, tax effect	[1]		$ (1.7)					$ (1.7)			$ 0.0
Net income		21.9					16.0					5.9
Other comprehensive income (loss)		(16.2)								(21.0)		4.8
Stock Repurchased During Period, Value		(50.0)			$ (1.1)	(14.9)	(34.0)
Stock Repurchased During Period, Shares					(1.1)
Dividends to:
Brink’s common shareholders ($0.80 per share)		(30.1)					(30.1)
Noncontrolling interests		(16.8)										(16.8)
Stock options and awards:
Compensation expense		31.3				31.3
Other share-based benefit transactions		(7.5)			$ 0.5	(7.9)	(0.1)
Other share-based benefit transactions (shares)					0.5
Acquisitions with noncontrolling interests		64.0										64.0
Ending Balance at Dec. 31, 2020		$ 202.5	$ 0.5	[2]	$ 49.5	671.8	407.5	$ 0.5	[2]	(1,000.0)		73.7
Ending Balance (shares) at Dec. 31, 2020					49.5
Stock options and awards:
Brink's common shareholders per share declared (dollars per share)		$ 0.60
Net income		$ 117.3					105.2					12.1
Other comprehensive income (loss)		89.5								92.1		(2.6)
Stock Repurchased During Period, Value		(200.0)			$ (2.4)	(34.6)	(163.0)
Stock Repurchased During Period, Shares					(2.4)
Brink’s common shareholders ($0.80 per share)		(37.2)					(37.2)
Noncontrolling interests		(5.1)										(5.1)
Compensation expense		33.1				33.1
Consideration from exercise of stock options		2.3				2.3
Other share-based benefit transactions		(1.8)			$ 0.3	(2.0)	(0.1)
Other share-based benefit transactions (shares)					0.3
Acquisitions with noncontrolling interests		51.4										51.4
Capital contributions from noncontrolling interest		0.1										0.1
Ending Balance at Dec. 31, 2021		$ 252.6			$ 47.4	670.6	312.9			(907.9)		129.6
Ending Balance (shares) at Dec. 31, 2021					47.4
Stock options and awards:
Brink's common shareholders per share declared (dollars per share)		$ 0.75
Net income		$ 181.9					170.6					11.3
Other comprehensive income (loss)		201.0								207.3		(6.3)
Stock Repurchased During Period, Value		(52.2)			$ (1.5)	(22.1)	(28.6)
Stock Repurchased During Period, Shares					(1.5)
Brink’s common shareholders ($0.80 per share)		(37.6)					(37.6)
Noncontrolling interests		(7.1)										(7.1)
Compensation expense		48.6				48.6
Other share-based benefit transactions		(9.4)			$ 0.4	(9.7)	(0.1)
Other share-based benefit transactions (shares)					0.4
Acquisitions of noncontrolling interests(c)	[3]	(7.8)				(3.3)				0.1		(4.6)
Acquisitions with noncontrolling interests		0.1										0.1
Capital contributions from noncontrolling interest		0.1										0.1
Ending Balance at Dec. 31, 2022		$ 570.2			$ 46.3	$ 684.1	$ 417.2			$ (700.5)		$ 123.1
Ending Balance (shares) at Dec. 31, 2022					46.3
Stock options and awards:
Brink's common shareholders per share declared (dollars per share)		$ 0.80

[1] Effective January 1, 2020, we adopted the provisions of ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. We recognized a cumulative effect adjustment to January 1, 2020 retained earnings as a result of adopting this standard. See Note 1 for further details.

[2] Effective January 1, 2021, we adopted the provisions of ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. We recognized a cumulative effect adjustment to January 1, 2021 retained earnings as a result of adopting this standard. See Note 1 for further details.

[3] This amount represents the impact of transactions in which we acquired or disposed of noncontrolling ownership interests in certain companies where we had an existing controlling interest prior to and after the related acquisition or disposal transactions.