Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Number of consumers the company facilitates money transfers between.

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Number of geographic regions whose functions are limited to generating, managing and maintaining agent relationships and localized marketing activities.

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Percentage of revenue allocated to the country where the transaction is initiated.

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Segments - Narrative (Details) $ in Millions	12 Months Ended
Segments - Narrative (Details) $ in Millions	Dec. 31, 2021 USD ($) Customer Segment Region	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Segments
Restructuring-related expenses and business transformation expenses	$ 152.3	$ 36.8	$ 115.5
Utilized to allocate revenue to the country where the transaction is initiated (as a percent)	100.00%
Operating Segments
Segments
Number of operating segments \| Segment	2
Operating Segments \| Consumer-to-Consumer
Segments
Number of consumers in money transfer \| Customer	2
Number of geographic regions in segment \| Region	5
Not Allocated To Segments
Segments
Restructuring-related expenses and business transformation expenses		$ 36.8	$ 115.5