Segments - Narrative (Details)	12 Months Ended
Dec. 31, 2022 Customer Region Segment
Segments
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

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Number of consumers the company facilitates money transfers between.

+ References

No definition available.

+ Details

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Namespace Prefix:	wu_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	wu_
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- Definition

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

+ References

No definition available.

+ Details

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- Details

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