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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% |  |  |  |  |  |  |

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