Related Party Transactions - Summary of Revenues from Advisory Services Provided to Related Parties (Detail) - Advisory Services [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Revenues from advisory services	$ 62,950	$ 64,840
WisdomTree Trust [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	39,601	42,223
Manjer Issuers [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	20,258	19,273
WisdomTree Multi Asset Issuer PLC And WisdomTree Issuer PLC [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	2,528	2,504
WisdomTree Asset Management Canada, Inc [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	365	546
WisdomTree Commodity Services LLC [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	$ 198	$ 294