v2.4.1.9

Deposits, Borrowed Federal Funds and Other Debt (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Banking and Thrift [Abstract]
Certificates of deposit with maturities within 1 year	$ 261,502wex_CertificateOfDepositsMaturitiesYearOne	$ 453,539wex_CertificateOfDepositsMaturitiesYearOne
Certificates of deposit with maturities greater than 1 year and less than 5 years	34,493wex_CertificateOfDepositsMaturitiesGreaterThanOneYearAndLessThanFiveYears	117,857wex_CertificateOfDepositsMaturitiesGreaterThanOneYearAndLessThanFiveYears
Interest-bearing money market deposits	330,696us-gaap_InterestBearingDomesticDepositMoneyMarket	222,546us-gaap_InterestBearingDomesticDepositMoneyMarket
Negotiable order of withdrawal deposits	314,576wex_NonInterestbearingDomesticDepositNegotiableOrderOfWithdrawalNow	276,422wex_NonInterestbearingDomesticDepositNegotiableOrderOfWithdrawalNow
Non-interest bearing customer deposits	38,286us-gaap_NoninterestBearingDepositLiabilitiesDomestic	18,566us-gaap_NoninterestBearingDepositLiabilitiesDomestic
Total deposits	$ 979,553us-gaap_Deposits	$ 1,088,930us-gaap_Deposits
Weighted average cost of funds on certificates of deposit outstanding	0.61%us-gaap_WeightedAverageRateDomesticDepositCertificatesOfDeposit	0.53%us-gaap_WeightedAverageRateDomesticDepositCertificatesOfDeposit
Weighted average cost of interest-bearing money market deposits	0.25%us-gaap_WeightedAverageRateDomesticDepositMoneyMarket	0.25%us-gaap_WeightedAverageRateDomesticDepositMoneyMarket
Weighted average cost of negotiable order of withdrawal deposits	0.00%wex_WeightedAverageRateDomesticDepositNegotiableOrderOfWithdrawalNow	0.00%wex_WeightedAverageRateDomesticDepositNegotiableOrderOfWithdrawalNow	0.00%wex_WeightedAverageRateDomesticDepositNegotiableOrderOfWithdrawalNow

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ 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 210.9-03.12)

-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

-Section 03

-Paragraph 12

-Article 9

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- Definition

Amount of interest-bearing domestic money market demand account deposit liabilities.

+ 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 210.9-03.12)

-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

-Section 03

-Paragraph 12

-Article 9

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Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

+ 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 210.9-03.12)

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



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

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

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The weighted average interest rate for domestic certificates of deposit liabilities.

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The weighted average interest rate for domestic money market demand account deposit liabilities.

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- Definition

Certificate of Deposits Maturities, Greater Than One Year And Less Than Five Years

+ References

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Certificate of Deposits Maturities, Year One

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Non Interest-bearing Domestic Deposit, Negotiable Order of Withdrawal (NOW)

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Weighted Average Rate Domestic Deposit Negotiable Order Of Withdrawal Now

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