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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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Cash and cash equivalents criteria maturity period.

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Increase Decrease In Current Assets

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Number Of Financial Institutions Cash And Cash Equivalents Are Held

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Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016 USD ($) Financial_Institution	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) Financial_Institution Segment	Jun. 30, 2015 USD ($)	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		1
ETF advisory fee revenue	$ 55,931	$ 81,320	$ 116,546	$ 141,189
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	651		$ 651		487
ETF advisory fee revenue	1,870	911	3,393	1,434
Wisdom Tree Issuer Plc [Member]
Related Party Transaction [Line Items]
Accounts receivable related-party	651		651		487
ETF advisory fee revenue	1,870	911	3,393	1,434
WisdomTree Trust [Member]
Related Party Transaction [Line Items]
Accounts receivable related-party	16,756		16,756		$ 24,560
ETF advisory fee revenue	53,587	$ 80,409	112,229	$ 139,755
WisdomTree Commodity Services LLC [Member]
Related Party Transaction [Line Items]
Accounts receivable related-party	162		162
ETF advisory fee revenue	474		924
WisdomTree Coal Services, LLC [Member]
Related Party Transaction [Line Items]
Accounts receivable related-party	162		162
ETF advisory fee revenue	$ 474		$ 924