Organization and Description of Business - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating income	$ 10,683	$ 13,221
WisdomTree Japan [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating income	(430)	$ (1,232)
Impairment of Leasehold	$ 572
Acquisition of ETFS Business [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Business Acquisition, Effective Date of Acquisition	Apr. 11, 2018

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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- Definition

The adjustment to reduce the value of existing agreements that specify the lessee's rights to use the leased property. This expense is charged when the estimates of future profits generated by the leased property are reduced.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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Organization Consolidation And Presentation Of Financial Statements [Line Items]

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No definition available.

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