Subsequent Events	9 Months Ended
Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn October 27, 2021, Brink’s announced that it intends to enter into an accelerated share repurchase ("ASR") agreement with J.P. Morgan Chase Bank, N.A., to repurchase $150 million of the company’s common stock. Brink's expects to execute the ASR as part of a $250 million share repurchase program authorized by its board of directors on February 6, 2020, which expires December 31, 2021 (see Note 12 for details). Also on October 27, 2021, Brink’s board of directors approved an additional $250 million of share repurchases, which expires December 31, 2023.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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