Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Estimated weighted average cost of capital.

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Fair Value Inputs Volatility

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Rate at which it represents the fair value of intangible assets Projected Growth

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Impairments - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended					12 Months Ended
	Dec. 29, 2017	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Intangible assets related to its customary advisory agreement		$ 603,294				$ 603,209	$ 603,294	$ 603,209
Impairment		30,138	$ 0	$ 0	$ 572	$ 17,386	30,710	17,386
WisdomTree Japan [Member]
Impairment							572	326
GreenHaven Commodity Services, LLC [Member]
Intangible assets related to its customary advisory agreement		$ 9,953					$ 9,953
Impairment								9,953
GreenHaven Commodity Services, LLC [Member] \| Revenue Growth Rate Maximum [Member]
Projected revenue growth rates							5.00%
GreenHaven Commodity Services, LLC [Member] \| Revenue Growth Rate Minimum [Member]
Projected revenue growth rates							0.00%
Advisor Engine [Member]
Impairment								$ 3,278
Weighted average cost of capital percentage	27.00%
Option volatility rate	40.00%