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.

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-Topic 310
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-Name Accounting Standards Codification
-Section 40
-Paragraph 7
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of gain (loss) on sale of accounts receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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The cash inflow associated with the proceeds from sale and collection of receivables during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-Publisher FASB
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- Definition

Deposits, HSA

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- Definition

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- Definition

HSA Assets Deposited and Managed by Third Party Depository Partners

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Off-Balance Sheet Arrangements (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
HSA assets amount serving as custodian	$ 5,200.0
HSA assets deposited and managed by third party depository partners	617.2
HSA deposits	4,574.0		$ 4,200.0
WEX Europe Services And WEX Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loss on sale of factoring receivables	$ 0.0	$ 0.0
WEX Europe Services
Accounts, Notes, Loans and Financing Receivable [Line Items]
Agreement termination minimum notification period	90 days
Proceeds from sale of factoring receivables	$ 82.6	112.3
WEX Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sale of factoring receivables	$ 1,300.0	$ 2,300.0
Termination notice period	30 days