XML 116 R97.htm IDEA: XBRL DOCUMENT v3.22.0.1

Derivatives - Unrealized Gains/(Losses) (Parenthetical) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Foreign Exchange Contract [Member]
Derivative [Line Items]
Gains/(losses) excluded from effectiveness testing recognized in other comprehensive income	$ (2.4)	$ 0.3	$ 1.5

X

- 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

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Gain/(Loss) excluded from effectiveness testing recognized in other comprehensive income based on an amortization approach

+ References

No definition available.

+ Details

Name:	wu_GainLossExcludedFromEffectivenessTestingRecognizedInOtherComprehensiveIncomeBasedOnAmortizationApproach
Namespace Prefix:	wu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: