v2.4.0.8

Reconciliation of Income and Share Data Used in Basic and Diluted Earnings Per Share Computations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Net earnings attributable to WEX Inc. available for common stockholders – Basic and Diluted	$ 43,838	$ 14,298	$ 114,740	$ 67,869
Weighted average common shares outstanding – Basic	38,978	38,793	38,934	38,832
Unvested restricted stock units	74	96	125	130
Stock options	29	106	43	122
Weighted average common shares outstanding – Diluted	39,081	38,995	39,102	39,084

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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257



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-Publisher FASB

-Name Accounting Standards Codification

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257



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-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1448-109256



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-Name Accounting Standards Codification

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Incremental common shares attributable to stock options.

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Incremental common shares attributable to unvested restricted stock units.

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Net income loss available to common stockholders basic and diluted.

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