Related Party Transactions - Summary of Revenues from Advisory Services Provided to Related Parties (Detail) - Advisory Services [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Revenues from advisory services	$ 265,652	$ 271,104	$ 226,692
WisdomTree Trust [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	169,483	203,031	215,513
Manjer Issuers [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	82,224	54,601
WisdomTree Multi Asset Issuer PLC And WisdomTree Issuer PLC [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	10,499	10,448	9,205
WisdomTree Asset Management Canada, Inc [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	2,440	1,757	466
WisdomTree Commodity Services LLC [Member]
Related Party Transaction [Line Items]
Revenues from advisory services	$ 1,006	$ 1,267	$ 1,508