v2.4.1.9

Sale of Subsidiary - Summary of Sale of Pacific Pride LLC (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 29, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale	$ 27,490us-gaap_GainOrLossOnSaleOfStockInSubsidiary	$ 0us-gaap_GainOrLossOnSaleOfStockInSubsidiary	$ 0us-gaap_GainOrLossOnSaleOfStockInSubsidiary
Pacific Pride
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received				49,664us-gaap_ProceedsFromDivestitureOfBusinesses / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Expenses associated with the sale				1,340wex_DisposalGroupNotDiscontinuedOperationExpensesrelatedtoSaleofBusiness / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Accounts receivable				48,699us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Accounts payable				(53,001)us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayable / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Other tangible assets and liabilities, net				828us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherLiabilities / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Goodwill				19,137us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill1 / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Gain on sale				27,490us-gaap_GainOrLossOnSaleOfStockInSubsidiary / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Customer relationships | Pacific Pride
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Intangible assets				3,727us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssets / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember
Trademarks and trade names | Pacific Pride
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Intangible assets				$ 1,444us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssets / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_TrademarksAndTradeNamesMember / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = wex_PacificPrideMember

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Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

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