Redeemable Non-Controlling Interest - Schedule of Redeemable Non-Controlling Interest (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance, beginning of period		$ 0		$ 0
Acquisition of Discovery Benefits at fair value				25,757
Establishing redeemable non-controlling interest for WEX Health at carrying value				32,843
Adjustment to redeemable non-controlling interest to reflect WEX Health at fair value	$ 17,720	$ 0		41,400
Accretion of non-controlling interest	17,720		$ 0	17,720	$ 0
Net income attributable to redeemable non-controlling interest				7
Balance, end of period	$ 117,727			$ 117,727

Amount of decrease (increase) in additional paid in capital (APIC) for the increase in carrying amount of redeemable preferred stock.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Net Increase or Decrease in balance of noncontrolling interest in the subsidiary during the reporting period.

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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Amount of increase in noncontrolling interest from a business combination.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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