v3.3.0.814

Earnings per Share - Reconciliation of Income and Share Data Used in Basic and Diluted Earnings Per Share Computations (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Net earnings attributable to WEX Inc. available for common stockholders – Basic and Diluted	$ 32,166	$ 74,443	$ 81,003	$ 154,318
Weighted average common shares outstanding – Basic (in shares)	38,745	38,867	38,780	38,896
Unvested restricted stock units (in shares)	46	74	55	85
Stock options (in shares)	17	20	17	23
Weighted average common shares outstanding – Diluted (in shares)	38,808	38,961	38,852	39,004

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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 45



-Paragraph 16



-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1505-109256



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



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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



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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 260



-SubTopic 10



-Section 45



-Paragraph 10



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



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



-Publisher FASB



-Name Accounting Standards Codification



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-URI http://asc.fasb.org/extlink&oid=6528421

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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) Attributable to Parent, After Accretion of Non-controlling Interest

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