Deferred Consideration - Schedule of Deferred Consideration (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Contractual gold payments									$ 17,096	$ 16,811	$ 13,226
Contractual gold payments – gold ounces paid									9,500	9,500	9,500
Gain/(loss) on revaluation of deferred consideration - gold payments	$ (3,048)	$ 1,737	$ 497	$ 2,832	$ (22,385)	$ (8,870)	$ (23,358)	$ (2,208)	$ 2,018	$ (56,821)	$ (11,293)

Gain/loss from revaluation of deferred consideration.

No definition available.

Name:	wetf_GainLossFromChangeInDeferredConsideration
Namespace Prefix:	wetf_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration