v2.4.1.9

Noncontrolling Interest - Reconciliation of Noncontrolling Interests (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance, beginning of period	$ 519us-gaap_MinorityInterest
Non-controlling interest investment	21,267wex_NoncontrollingInterestinJointVenturesInvestmentsduringPeriod	1,032wex_NoncontrollingInterestinJointVenturesInvestmentsduringPeriod
Net loss attributable to non-controlling interest	(2,193)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(910)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(213)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest
Ending balance	17,396us-gaap_MinorityInterest	519us-gaap_MinorityInterest
WEX Europe Services
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance, beginning of period	519us-gaap_MinorityInterest / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember	0us-gaap_MinorityInterest / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember
Non-controlling interest investment	21,267wex_NoncontrollingInterestinJointVenturesInvestmentsduringPeriod / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember	1,032wex_NoncontrollingInterestinJointVenturesInvestmentsduringPeriod / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember
Net loss attributable to non-controlling interest	(2,391)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember	(509)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember
Currency translation adjustment	(1,999)wex_NoncontrollingInterestForeignCurrencyTranslationAdjustment / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember	(4)wex_NoncontrollingInterestForeignCurrencyTranslationAdjustment / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember
Ending balance	$ 17,396us-gaap_MinorityInterest / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember	$ 519us-gaap_MinorityInterest / us-gaap_BusinessAcquisitionAxis = wex_WEXEuropeServicesMember

X

- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 27

-Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 20

-Article 7

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X

- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 55

-Paragraph 4J

-URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4591551-111686

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- Definition

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+ References

No definition available.

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X

- Definition

Noncontrolling Interest in Joint Ventures, Investments during Period

+ References

No definition available.

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