v2.4.1.9
Goodwill and Other Intangible Assets - Additional Information (Details) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended 0 Months Ended 3 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Sep. 30, 2012
Dec. 31, 2012
Sep. 30, 2012
Dec. 31, 2013
Goodwill And Other Intangible Assets [Line Items]              
Goodwill impairment loss $ 0us-gaap_GoodwillImpairmentLoss $ 0us-gaap_GoodwillImpairmentLoss $ 17,508us-gaap_GoodwillImpairmentLoss        
Wright Express Prepaid Australia              
Goodwill And Other Intangible Assets [Line Items]              
Goodwill impairment loss       16,171us-gaap_GoodwillImpairmentLoss
/ us-gaap_BusinessAcquisitionAxis
= wex_WrightExpressPrepaidAustraliaMember		      
Financial Automation Limited              
Goodwill And Other Intangible Assets [Line Items]              
Goodwill impairment loss         $ 1,337us-gaap_GoodwillImpairmentLoss
/ us-gaap_BusinessAcquisitionAxis
= wex_FinancialAutomationLimitedMember		 $ 1,337us-gaap_GoodwillImpairmentLoss
/ us-gaap_BusinessAcquisitionAxis
= wex_FinancialAutomationLimitedMember		  
WEX Brand | Trademarks, trade names and brand names              
Goodwill And Other Intangible Assets [Line Items]              
Useful life             10 years