v2.4.1.9

Financing Debt - Additional Information - 2011 Credit Agreement (Details) (USD $)	3 Months Ended	12 Months Ended			3 Months Ended	0 Months Ended
	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2011	May 23, 2011
Debt Instrument [Line Items]
Credit agreement loan, maximum		$ 125,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity	$ 125,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Deferred finance costs, net			15,547,000us-gaap_DeferredFinanceCostsNet
Previous issuance costs, wrote-off	1,000,000us-gaap_WriteOffOfDeferredDebtIssuanceCost	0us-gaap_WriteOffOfDeferredDebtIssuanceCost	1,004,000us-gaap_WriteOffOfDeferredDebtIssuanceCost	0us-gaap_WriteOffOfDeferredDebtIssuanceCost
2011 Credit Agreement
Debt Instrument [Line Items]
Availability under credit agreement						150,000,000us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
Deferred finance costs, net						6,200,000us-gaap_DeferredFinanceCostsNet / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
Previous issuance costs, wrote-off					700,000us-gaap_WriteOffOfDeferredDebtIssuanceCost / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
2011 Credit Agreement | Term Loans Facility
Debt Instrument [Line Items]
Credit agreement loan, term						5 years
Credit agreement loan, maximum						200,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
Payment due for term loan facility						2,500,000us-gaap_LineOfCreditFacilityPeriodicPayment / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
2011 Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement loan, term						5 years
Credit agreement loan, maximum						700,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
2011 Credit Agreement | Revolving Credit Facility | Letter of Credit
Debt Instrument [Line Items]
Credit agreement loan, maximum						$ 100,000,000us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_ShortTermDebtTypeAxis = us-gaap_LetterOfCreditMember

X

- Details

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

X

- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Balance Type:	credit
Period Type:	instant

X

- Definition

Amount of the required periodic payments of both interest and principal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Balance Type:	debit
Period Type:	duration

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Balance Type:	credit
Period Type:	instant

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

Line of credit facility. term of credit

+ References

No definition available.

+ Details

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