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
Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]
Net earnings attributable to WEX Inc. available for common stockholders – Basic and Diluted	$ 36,542	$ 28,689
Weighted average common shares outstanding – Basic	38,966	38,888
Unvested restricted stock units	153	242
Stock options	26	57
Weighted average common shares outstanding – Diluted	39,145	39,187

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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

+ Details

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- Definition

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

-Glossary Weighted-Average Number of Common Shares Outstanding

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

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- Definition

Incremental common shares attributable to stock options.

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No definition available.

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- Definition

Incremental common shares attributable to unvested restricted stock units.

+ References

No definition available.

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- Definition

Net income loss available to common stockholders basic and diluted.

+ References

No definition available.

+ Details

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