XML 155 R134.htm IDEA: XBRL DOCUMENT
v3.20.4

Impairments - Additional Information (Detail) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 29, 2017 | Sep. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Intangible assets related to its customary advisory agreement |  |  |  | $ 603,294 |  | $ 601,247 | $ 603,294 |
Impairment |  | $ 3,080 | $ 19,672 | $ 30,138 | $ 572 | 22,752 | 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 |  |
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% |  |  |  |  |  |  |

X
- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
Name: | us-gaap_AssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
Name: | us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Estimated weighted average cost of capital. + References No definition available. + Details
Name: | wetf_EstimatedWeightedAverageCostOfCapital
Namespace Prefix: | wetf_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair Value Inputs Volatility + References No definition available. + Details
Name: | wetf_FairValueInputsVolatility
Namespace Prefix: | wetf_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Rate at which it represents the fair value of intangible assets Projected Growth + References No definition available. + Details
Name: | wetf_FairValueOfIntangibleAsset
Namespace Prefix: | wetf_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=wetf_WisdomTreeJapanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=wetf_GreenHavenCommodityServicesLlcMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=wetf_AdvisorEngineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |