v2.4.1.9

- Schedule Of Balance Outstanding On Revolving Line-Of-Credit Facility And Term Loan (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Jan. 30, 2013
Line of Credit Facility [Line Items]
Outstanding borrowings against federal funds lines-of-credit	$ 901,564,000us-gaap_LineOfCredit	$ 285,000,000us-gaap_LineOfCredit
Senior notes	400,000,000us-gaap_SeniorNotes	400,000,000us-gaap_SeniorNotes
Long-term Debt	1,301,564,000us-gaap_LongTermDebt	685,000,000us-gaap_LongTermDebt
Senior Notes
Line of Credit Facility [Line Items]
Senior notes			400,000,000us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = us-gaap_SeniorNotesMember
2013 Credit Agreement | Senior Notes
Line of Credit Facility [Line Items]
Senior notes	400,000,000us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = us-gaap_SeniorNotesMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	400,000,000us-gaap_SeniorNotes / us-gaap_DebtInstrumentAxis = us-gaap_SeniorNotesMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember
London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Outstanding borrowings against federal funds lines-of-credit	696,250,000us-gaap_LineOfCredit / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	285,000,000us-gaap_LineOfCredit / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
Interest rate	2.92%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	1.93%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
Prime Rate
Line of Credit Facility [Line Items]
Outstanding borrowings against federal funds lines-of-credit	67,700,000us-gaap_LineOfCredit / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	0us-gaap_LineOfCredit / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
Interest rate	5.00%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	0.00%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
Eurocurrency Rate
Line of Credit Facility [Line Items]
Outstanding borrowings against federal funds lines-of-credit	$ 137,614,000us-gaap_LineOfCredit / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	$ 0us-gaap_LineOfCredit / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember
Interest rate	2.88%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	0.00%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember

X

- Definition

The average effective interest rate during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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+ Details

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X

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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

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-Name Accounting Standards Codification

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+ Details

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X

- Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

X

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Publisher FASB

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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Period Type:	instant

X

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a))

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

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-Article 9

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Period Type:	instant

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=wex_TwoThousandAndThirteenCreditAgreementMember
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- Details

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- Details

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