XML 118 R101.htm IDEA: XBRL DOCUMENT v3.10.0.1

Goodwill and Intangible Assets - Additional Information (Detail) $ in Thousands, $ in Thousands			3 Months Ended		6 Months Ended
	Apr. 30, 2018 USD ($)	Apr. 11, 2018 USD ($)	Dec. 31, 2017 USD ($) Fund	Dec. 31, 2017 CAD ($) Fund	Jun. 30, 2018 USD ($)	Jan. 01, 2016 USD ($)
Indefinite-lived Intangible Assets [Line Items]
Intangible asset related to its customary advisory agreement			$ 12,085		$ 613,227
U.S. Business segment [Member]
Indefinite-lived Intangible Assets [Line Items]
Goodwill, impairment loss	$ 0
Questrade ETFs [Member]
Indefinite-lived Intangible Assets [Line Items]
Intangible asset related to its customary advisory agreement			$ 2,132		2,027
Questrade ETFs [Member] | WisdomTree Asset Management Canada, Inc [Member]
Indefinite-lived Intangible Assets [Line Items]
Number of ETF acquired by company | Fund			8	8
Assets under management			$ 77,403	$ 99,108
Business acquisition, cash paid			2,132	$ 2,675
GreenHaven Commodity Services, LLC [Member]
Indefinite-lived Intangible Assets [Line Items]
Intangible asset related to its customary advisory agreement			$ 9,953		9,953	$ 9,953
GreenHaven Commodity Services, LLC [Member] | U.S. Business segment [Member]
Indefinite-lived Intangible Assets [Line Items]
Goodwill acquired					$ 1,799
Acquisition of ETFS Business [Member]
Indefinite-lived Intangible Assets [Line Items]
Acquisition completion date					Apr. 11, 2018
Goodwill acquired					$ 84,057
Intangible asset related to its customary advisory agreement					$ 601,247
Weighted average cost of capital percentage		11.60%
Business acquisition, cash paid		$ 253,000
Acquisition of ETFS Business [Member] | Minimum [Member]
Indefinite-lived Intangible Assets [Line Items]
Revenue growth multiple		3.00%
Acquisition of ETFS Business [Member] | Maximum [Member]
Indefinite-lived Intangible Assets [Line Items]
Revenue growth multiple		4.00%

X

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e848-128460

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e845-128460

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillAcquiredDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13854-109267

Reference 2: 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=109223946&loc=d3e3602-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266

+ Details

Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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

The cash outflow to acquire asset without physical form usually arising from contractual or other legal rights, excluding 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 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireIntangibleAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Assets under management of the eight Questrade ETFs being acquired and managed by the Company.

+ References

No definition available.

+ Details

Name:	wetf_AssetsUnderManagementOfRelatedPartyAcquiredAndManagedByEntity
Namespace Prefix:	wetf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

Number of exchange traded fund.

+ References

No definition available.

+ Details

Name:	wetf_NumberOfExchangeTradedFund
Namespace Prefix:	wetf_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage Of Revenue Growth

+ References

No definition available.

+ Details

Name:	wetf_PercentageOfRevenueGrowth
Namespace Prefix:	wetf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=wetf_USBusinessSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=wetf_QuestradeETFsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=wetf_WisdomtreeAssetManagementCanadaIncMember
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:	us-gaap_BusinessAcquisitionAxis=wetf_AcquisitionOfEtfsBusinessMember
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_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: