v2.4.1.9

Income Taxes - Net Deferred Tax Assets By Jurisdiction (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Components Of Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Net, Total	$ (37,988)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 75,437us-gaap_DeferredTaxAssetsLiabilitiesNet
United States
Components Of Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Net, Total	(34,963)us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_US	87,940us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_US
Australia
Components Of Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Net, Total	(7,078)us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_AU	(9,438)us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_AU
New Zealand
Components Of Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Net, Total	185us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_NZ	45us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_NZ
The Netherlands
Components Of Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Net, Total	238us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_NL	89us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_NL
United Kingdom
Components Of Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Net, Total	5,607us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_GB	57us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_GB
Brazil
Components Of Deferred Tax Assets And Liabilities [Line Items]
Deferred Tax Assets, Net, Total	$ (1,977)us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_BR	$ (3,256)us-gaap_DeferredTaxAssetsLiabilitiesNet / us-gaap_IncomeTaxAuthorityAxis = country_BR

X

- Definition

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

+ Details

Name:	us-gaap_DeferredTaxAssetsLiabilitiesNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	wex_ComponentsOfDeferredTaxAssetsAndLiabilitiesLineItems
Namespace Prefix:	wex_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=country_AU
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=country_BR
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=country_GB
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=country_NL
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=country_NZ
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: