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Contingent Payments - Additional Information (Detail) $ in Thousands, $ in Thousands			3 Months Ended
	Feb. 19, 2020 USD ($)	Feb. 19, 2020 CAD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2021 CAD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 CAD ($)	May 04, 2020 USD ($)
Recognized gain loss on sale of business					$ 2,877
Impairment			$ 303		19,672
WisdomTree Asset Management Canada, Inc [Member]
Other receivables						$ 2,000		$ 2,000
Proceeds from divestiture of businesses	$ 2,774	$ 3,720
Recognized gain loss on sale of business					2,877
WisdomTree Asset Management Canada, Inc [Member] \| Minimum [Member]
Additional consideration payable		2,000
WisdomTree Asset Management Canada, Inc [Member] \| Maximum [Member]
Additional consideration payable		$ 8,000
Advisor Engine [Member]
Maximum Amount of Contingent Payments That May be Received									$ 10,408
Contingent payments			$ 0				$ 0
Gain (Loss) on Disposition of Assets				$ 1,093
Advisor Engine [Member] \| Fair Value Of Upfront Consideration Received [Member]
Fair value of upfront consideration received									$ 9,592
Advisor Engine Financial Interest [Member] \| Financial Interests [Member]
Impairment					$ 19,672