v2.4.1.9

Financing Debt - Components Of Financing Interest Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended			3 Months Ended
	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2011
Line of Credit Facility [Line Items]
Total financing interest expense		$ 36,042us-gaap_FinancingInterestExpense	$ 29,419us-gaap_FinancingInterestExpense	$ 10,433us-gaap_FinancingInterestExpense
Realized losses on interest rate swaps		0us-gaap_GainLossOnInterestRateCashFlowHedgeIneffectiveness	0us-gaap_GainLossOnInterestRateCashFlowHedgeIneffectiveness	109us-gaap_GainLossOnInterestRateCashFlowHedgeIneffectiveness
Previous issuance costs, wrote-off	1,000us-gaap_WriteOffOfDeferredDebtIssuanceCost	0us-gaap_WriteOffOfDeferredDebtIssuanceCost	1,004us-gaap_WriteOffOfDeferredDebtIssuanceCost	0us-gaap_WriteOffOfDeferredDebtIssuanceCost
Other		0us-gaap_InterestExpenseOtherShortTermBorrowings	1us-gaap_InterestExpenseOtherShortTermBorrowings	33us-gaap_InterestExpenseOtherShortTermBorrowings
Average other debt (UNIK and participation agreement)		37,876us-gaap_LineOfCreditFacilityAverageOutstandingAmount	8,767us-gaap_LineOfCreditFacilityAverageOutstandingAmount	9,823us-gaap_LineOfCreditFacilityAverageOutstandingAmount
2014 Credit Agreement
Line of Credit Facility [Line Items]
Total financing interest expense		9,230us-gaap_FinancingInterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0us-gaap_FinancingInterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0us-gaap_FinancingInterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember
2011 Credit Agreement
Line of Credit Facility [Line Items]
Total financing interest expense		0us-gaap_FinancingInterestExpense / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	664us-gaap_FinancingInterestExpense / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	10,291us-gaap_FinancingInterestExpense / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
Previous issuance costs, wrote-off					700us-gaap_WriteOffOfDeferredDebtIssuanceCost / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
2013 Credit Agreement
Line of Credit Facility [Line Items]
Total financing interest expense		7,078us-gaap_FinancingInterestExpense / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	9,607us-gaap_FinancingInterestExpense / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	0us-gaap_FinancingInterestExpense / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember
Revolving Credit Facility | 2014 Credit Agreement
Line of Credit Facility [Line Items]
Fees		733wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember
Amortization of loan origination fees		574wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember
Revolving Credit Facility | 2011 Credit Agreement
Line of Credit Facility [Line Items]
Fees		0wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	36wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	1,369wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
Amortization of loan origination fees		0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	43wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	1,100wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
Revolving Credit Facility | 2013 Credit Agreement
Line of Credit Facility [Line Items]
Fees		1,361wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	2,098wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	0wex_InterestExpenseFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember
Amortization of loan origination fees		757wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	1,122wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember
Term Loans Facility | 2014 Credit Agreement
Line of Credit Facility [Line Items]
Amortization of loan origination fees		276wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember	0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember
Term Loans Facility | 2011 Credit Agreement
Line of Credit Facility [Line Items]
Amortization of loan origination fees		0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	11wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember	297wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember
Term Loans Facility | 2013 Credit Agreement
Line of Credit Facility [Line Items]
Amortization of loan origination fees		301wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	491wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember	0wex_AmortizationOfLoanOriginationFees / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember
Eurocurrency Rate
Line of Credit Facility [Line Items]
Average interest rate (including impact of interest rate swaps):		2.81%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	0.00%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	0.00%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember
Average other debt (UNIK and participation agreement)		17,216us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	0us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	0us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember
Eurocurrency Rate | Revolving Credit Facility | 2014 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		484us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = wex_EurocurrencyRateMember
London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Average interest rate (including impact of interest rate swaps):		2.30%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	1.93%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	1.79%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
Average other debt (UNIK and participation agreement)		452,911us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	300,056us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	366,387us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
London Interbank Offered Rate (LIBOR) | Revolving Credit Facility | 2014 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		1,723us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
London Interbank Offered Rate (LIBOR) | Revolving Credit Facility | 2011 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	350us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	3,103us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
London Interbank Offered Rate (LIBOR) | Revolving Credit Facility | 2013 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		573us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	400us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
London Interbank Offered Rate (LIBOR) | Term Loans Facility | 2014 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		4,468us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
London Interbank Offered Rate (LIBOR) | Term Loans Facility | 2011 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	170us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	3,339us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
London Interbank Offered Rate (LIBOR) | Term Loans Facility | 2013 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		3,667us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	5,496us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = wex_CreditFacilityTermLoansMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndThirteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
Prime Rate
Line of Credit Facility [Line Items]
Average interest rate (including impact of interest rate swaps):		3.89%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	3.75%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	3.75%us-gaap_LineOfCreditFacilityInterestRateDuringPeriod / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
Average other debt (UNIK and participation agreement)		35,765us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	19,162us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	28,885us-gaap_LineOfCreditFacilityAverageOutstandingAmount / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
Prime Rate | Revolving Credit Facility | 2014 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		972us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
Prime Rate | Revolving Credit Facility | 2011 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		0us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	54us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember	1,083us-gaap_InterestExpense / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_LineOfCreditFacilityAxis = wex_TwoThousandAndElevenCreditAgreementMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
Senior Notes | 2014 Credit Agreement
Line of Credit Facility [Line Items]
Interest Expense		19,000us-gaap_InterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember	17,469us-gaap_InterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember	0us-gaap_InterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember
Amortization of loan origination fees		734wex_AmortizationOfLoanOriginationFees / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember	674wex_AmortizationOfLoanOriginationFees / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember	0wex_AmortizationOfLoanOriginationFees / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember
Total financing interest expense		$ 19,734us-gaap_FinancingInterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember	$ 18,143us-gaap_FinancingInterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember	$ 0us-gaap_FinancingInterestExpense / us-gaap_DebtInstrumentAxis = wex_TwoThousandAndFourteenCreditAgreementMember / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember

X

- Definition

This element represents interest incurred for borrowed money which was used to produce goods or render services.

+ 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 210.5-03.2)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 2

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The net gain (loss) during the reporting period due to ineffectiveness in interest rate cash flow hedges. Recognized in earnings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)(1)

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 942

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-Name Regulation S-X (SX)

-Number 210

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Name:	us-gaap_InterestExpense
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Interest expense incurred during the reporting period on other short-term borrowings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.7)

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Name:	us-gaap_InterestExpenseOtherShortTermBorrowings
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityAverageOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

The effective interest rate during the reporting period.

+ 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))

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-Name Regulation S-X (SX)

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-Section 02

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X

- Details

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X

- 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)

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