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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
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- Definition

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
-Paragraph 5
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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
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-Topic 230
-SubTopic 10
-Section 45
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-Publisher FASB
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Accounts Receivable Factoring Agreement, Renewal Term

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- Definition

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- Definition

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HSA Assets Deposited and Managed by Third Party Depository Partners

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Termination Notice Period

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Off-Balance Sheet Arrangements (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Renewal term				1 year
HSA assets amount serving as custodian		$ 4,200.0		$ 4,200.0
HSA assets deposited and managed by third party depository partners		1,000.0		1,000.0
HSA deposits		3,270.0		3,270.0		$ 3,020.0
WEX Europe Services
Accounts, Notes, Loans and Financing Receivable [Line Items]
Losses on factoring		3.3	$ 2.6	6.5	$ 4.5
Proceeds from sale of factoring receivables		137.1	142.9	267.7	283.4
WEX Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sale of factoring receivables		$ 5,300.0	3,300.0	$ 9,800.0	5,200.0
WEX Health
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sale of factoring receivables			$ 82.2		$ 82.2
WEX Health \| Revolving Credit Facility \| Securitized debt
Accounts, Notes, Loans and Financing Receivable [Line Items]
Borrowing capacity	$ 35.0
Additional extension period	3 years
Termination notice period	30 days