v2.4.1.9

Accounts Receivable and Reserves for Credit Losses - Additional Information (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade receivable payments terms	30 days
Percent of total, current and less than 30 days past due	94.00%wex_PercentageOfFinancingReceivableRecordedInvestmentCurrent	95.00%wex_PercentageOfFinancingReceivableRecordedInvestmentCurrent
Percent of total, outstanding balances within 60 days	98.00%wex_PercentageofTradeReceivablesOutstandingBalancesLessThan60Days	99.00%wex_PercentageofTradeReceivablesOutstandingBalancesLessThan60Days
Accounts Receivable | Customer Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of customers	0wex_ConcentrationRiskNumberofCustomers / us-gaap_ConcentrationRiskByBenchmarkAxis = us-gaap_AccountsReceivableMember / us-gaap_ConcentrationRiskByTypeAxis = us-gaap_CustomerConcentrationRiskMember
Percentage of outstanding receivables (no more than 10 percent)	10.00%us-gaap_ConcentrationRiskPercentage1 / us-gaap_ConcentrationRiskByBenchmarkAxis = us-gaap_AccountsReceivableMember / us-gaap_ConcentrationRiskByTypeAxis = us-gaap_CustomerConcentrationRiskMember

X

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Concentration Risk, Number of Customers

+ References

No definition available.

+ Details

Name:	wex_ConcentrationRiskNumberofCustomers
Namespace Prefix:	wex_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Percentage of financing receivable, recorded investment, current

+ References

No definition available.

+ Details

Name:	wex_PercentageOfFinancingReceivableRecordedInvestmentCurrent
Namespace Prefix:	wex_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Percentage of Trade Receivables, Outstanding Balances Less Than 60 Days

+ References

No definition available.

+ Details

Name:	wex_PercentageofTradeReceivablesOutstandingBalancesLessThan60Days
Namespace Prefix:	wex_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Trade receivable payments period.

+ References

No definition available.

+ Details

Name:	wex_TradeReceivablePaymentsPeriod
Namespace Prefix:	wex_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: