For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Amount of fees earned from providing investment advice and research to customers.

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Cash and cash equivalents criteria maturity period.

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Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016 USD ($) Financial_Institution Segment	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Related Party Transaction [Line Items]
Cash and cash equivalents maturity period, maximum	90 days
Number of financial institutions \| Financial_Institution	1
ETF advisory fee revenue	$ 60,615	$ 59,869
Number of operating segments \| Segment	1
Adjustments for New Accounting Principle, Early Adoption [Member]
Related Party Transaction [Line Items]
Reduction in current assets			$ 9,279
Boost Issuer PLC [Member]
Related Party Transaction [Line Items]
Accounts receivable related-party	$ 578		487
ETF advisory fee revenue	1,523	523
Wisdom Tree Issuer Plc [Member]
Related Party Transaction [Line Items]
Accounts receivable related-party	578		487
ETF advisory fee revenue	1,523	523
WisdomTree Trust [Member]
Related Party Transaction [Line Items]
Accounts receivable related-party	19,663		$ 24,560
ETF advisory fee revenue	$ 58,642	$ 59,346