v2.4.1.9

Business Acquisitions and Other Intangible Assets Acquisitions - Additional Information - Esso Portfolio Acquisition (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended			0 Months Ended	1 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	Dec. 01, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Consideration paid (net of cash acquired)									$ 891,725us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired	$ 11,277us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired	$ 402,475us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired
Net 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
Net earnings attributable to WEX Inc.	(47,893)us-gaap_NetIncomeLoss	(74,443)us-gaap_NetIncomeLoss	(43,333)us-gaap_NetIncomeLoss	(36,542)us-gaap_NetIncomeLoss	(34,468)us-gaap_NetIncomeLoss	(43,838)us-gaap_NetIncomeLoss	(42,213)us-gaap_NetIncomeLoss	(28,689)us-gaap_NetIncomeLoss	(202,211)us-gaap_NetIncomeLoss	(149,208)us-gaap_NetIncomeLoss	(96,922)us-gaap_NetIncomeLoss
ESSO Portfolio
Business Acquisition [Line Items]
Percent of ownership interest acquired												75.00%us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired / us-gaap_BusinessAcquisitionAxis = wex_ESSOPortfolioMember
Consideration paid (net of cash acquired)												378,470us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired / us-gaap_BusinessAcquisitionAxis = wex_ESSOPortfolioMember
Advanced payment	80,000us-gaap_PaymentsToAcquireBusinessesGross / us-gaap_BusinessAcquisitionAxis = wex_ESSOPortfolioMember
Net revenues													3,428us-gaap_SalesRevenueNet / us-gaap_BusinessAcquisitionAxis = wex_ESSOPortfolioMember
Net earnings attributable to WEX Inc.													$ 7,172us-gaap_NetIncomeLoss / us-gaap_BusinessAcquisitionAxis = wex_ESSOPortfolioMember

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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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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