Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569655-111683

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4616395-111683

Name:	us-gaap_MinorityInterestDecreaseFromRedemptions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Non-controlling interests - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Aug. 31, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Aug. 30, 2012
Noncontrolling Interest [Line Items]
Purchase of non-controlling interest		$ 46,018	$ 0	$ 46,018	$ 0
Unik [Member]
Noncontrolling Interest [Line Items]
Percent of ownership interest acquired	49.00%					51.00%
Purchase of non-controlling interest	$ 46,018
WEX Europe Services [Member]
Noncontrolling Interest [Line Items]
Percent of ownership interest acquired		75.00%		75.00%