Consolidated Statement of Equity - USD ($) shares in Millions, $ in Millions		Total	Cumulative Effect, Period of Adoption, Adjustment	[1]	Common Stock	Capital in Excess of Par Value	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	[1]	AOCI*	Noncontrolling Interests
Beginning Balance at Dec. 31, 2020		$ 202.5	$ 0.5		$ 49.5	$ 671.8	$ 407.5	$ 0.5		$ (1,000.0)	$ 73.7
Beginning Balance (shares) at Dec. 31, 2020					49.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
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)
Dividends to:
Brink's common shareholders		(37.2)					(37.2)
Noncontrolling interests		(5.1)									(5.1)
Stock options and awards:
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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
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)
Dividends to:
Brink's common shareholders		(37.6)					(37.6)
Noncontrolling interests		(7.1)									(7.1)
Stock options and awards:
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	[2]	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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		98.3					87.7				10.6
Other comprehensive income (loss)		42.2								44.5	(2.3)
Stock Repurchased During Period, Value	[3]	(173.3)			$ (2.3)	(38.9)	(132.1)
Stock Repurchased During Period, Shares	[3]				(2.3)
Dividends to:
Brink's common shareholders		(39.6)					(39.6)
Noncontrolling interests		(7.7)									(7.7)
Stock options and awards:
Compensation expense		32.1				32.1
Other share-based benefit transactions		(1.4)			$ 0.5	(1.7)	(0.2)
Other share-based benefit transactions (shares)					0.5
Acquisitions of noncontrolling interests		(0.6)				0.3				0.0	(0.9)
Ending Balance at Dec. 31, 2023		$ 520.2			$ 44.5	$ 675.9	$ 333.0			$ (656.0)	$ 122.8
Ending Balance (shares) at Dec. 31, 2023					44.5

[1] 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.

[2] 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.

[3] During 2023, we repurchased a total of 2,297,955 shares of our common stock for an aggregate of $169.9 million in cash. On the last two days of December 2023, our agent broker purchased additional shares of our common stock pursuant to a trading plan in accordance with Rule 10b5-1 under the Securities Exchange Act of 1934, as amended. We are obligated to pay $2.0 million to repurchase those shares and, as of December 31, 2023, this obligation has been reported as a current liability and a corresponding reduction to equity in our condensed consolidated financial statements. For year ended December 31, 2023, shares repurchased include the 1% excise tax imposed under the Inflation Reduction Act of 2022 of approximately $1.4 million.