Redeemable Non-Controlling Interest - Schedule of Redeemable Non-Controlling Interest (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance, beginning of period	$ 156,879	$ 0
Acquisition of Discovery Benefits at fair value	0	25,757
Establishing redeemable non-controlling interest for WEX Health at carrying value	0	32,843
Adjustment to redeemable non-controlling interest to reflect WEX Health at fair value	0	41,400
Net income (loss) attributable to redeemable non-controlling interest	142	(7)
Accretion of non-controlling interest		0
Balance, end of period	$ 159,645	$ 99,993

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

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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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- Definition

Amount of increase in noncontrolling interest from a business combination.

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- Definition

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

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- Definition

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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- Definition

Value of accretion of temporary equity to its redemption value during the period.

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