v3.3.0.814
Non-controlling interests - Schedules of Non-controlling Interest (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Reconcilliation of Redeemable Noncontrolling Interest [Roll Forward]        
Balance, beginning of period $ 14,992 $ 19,732 $ 16,590 $ 18,729
Net gain (loss) attributable to redeemable non-controlling interest 531 218 1,190 (31)
Currency translation adjustment (1,953) (1,967) (4,210) (715)
Adjustment to redemption value 9,413 0 9,413 0
Excess purchase amount over redemption value 23,035 0 23,035 0
Purchase of non-controlling interest (46,018) 0 (46,018) 0
Ending balance 0 17,983 0 17,983
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]        
Balance, beginning of period     17,396  
Net loss attributable to non-controlling interest 203 (593) (2,201) (1,539)
Ending balance 12,332   12,332  
WEX Europe Services [Member]        
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]        
Balance, beginning of period 13,165 859 17,396 519
Non-controlling interest investment 0 20,234 0 21,267
Net loss attributable to non-controlling interest (328) (811) (3,391) (1,508)
Currency translation adjustment (505) (1,011) (1,673) (1,007)
Ending balance $ 12,332 $ 19,271 $ 12,332 $ 19,271