v2.4.1.9

Segment Information - Schedule Of Revenue By Geographic Data (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues	$ 211,864us-gaap_SalesRevenueNet		$ 222,134us-gaap_SalesRevenueNet	$ 201,581us-gaap_SalesRevenueNet	$ 182,068us-gaap_SalesRevenueNet	$ 182,283us-gaap_SalesRevenueNet		$ 191,525us-gaap_SalesRevenueNet	$ 178,285us-gaap_SalesRevenueNet	$ 165,370us-gaap_SalesRevenueNet	$ 817,647us-gaap_SalesRevenueNet		$ 717,463us-gaap_SalesRevenueNet		$ 623,151us-gaap_SalesRevenueNet
Goodwill	1,116,365us-gaap_Goodwill	[1]				819,892us-gaap_Goodwill	[1]				1,116,365us-gaap_Goodwill	[1]	819,892us-gaap_Goodwill	[1]	847,986us-gaap_Goodwill
Total other intangibles assets, net	498,045us-gaap_OtherIntangibleAssetsNet					206,744us-gaap_OtherIntangibleAssetsNet					498,045us-gaap_OtherIntangibleAssetsNet		206,744us-gaap_OtherIntangibleAssetsNet		241,950us-gaap_OtherIntangibleAssetsNet
Property, equipment and capitalized software, net	105,596us-gaap_PropertyPlantAndEquipmentNet					72,275us-gaap_PropertyPlantAndEquipmentNet					105,596us-gaap_PropertyPlantAndEquipmentNet		72,275us-gaap_PropertyPlantAndEquipmentNet		60,097us-gaap_PropertyPlantAndEquipmentNet
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues											708,827us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_US		627,282us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_US		541,404us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_US
Goodwill	866,313us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_US					589,319us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_US					866,313us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_US		589,319us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_US		589,319us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_US
Total other intangibles assets, net	388,717us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_US					118,808us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_US					388,717us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_US		118,808us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_US		135,386us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_US
Property, equipment and capitalized software, net	72,334us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US					59,817us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US					72,334us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US		59,817us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US		47,915us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US
Australia
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues											57,897us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_AU		61,645us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_AU		68,932us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = country_AU
Goodwill	165,688us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_AU					180,274us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_AU					165,688us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_AU		180,274us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_AU		210,746us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = country_AU
Total other intangibles assets, net	32,123us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_AU					43,385us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_AU					32,123us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_AU		43,385us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_AU		62,757us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = country_AU
Property, equipment and capitalized software, net	6,280us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_AU					5,988us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_AU					6,280us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_AU		5,988us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_AU		7,383us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_AU
International
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues											50,923us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember		28,536us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember		12,815us-gaap_SalesRevenueNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember
Goodwill	84,364us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = wex_InternationalMember					50,299us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = wex_InternationalMember					84,364us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = wex_InternationalMember		50,299us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = wex_InternationalMember		47,921us-gaap_Goodwill / us-gaap_StatementGeographicalAxis = wex_InternationalMember
Total other intangibles assets, net	77,205us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember					44,551us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember					77,205us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember		44,551us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember		43,807us-gaap_OtherIntangibleAssetsNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember
Property, equipment and capitalized software, net	$ 26,982us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember					$ 6,470us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember					$ 26,982us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember		$ 6,470us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember		$ 4,799us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = wex_InternationalMember
[1] The prior year amounts have been adjusted to reflect changes as a result of finalizing the purchase accounting.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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