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
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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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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- Definition

Organization Consolidation And Presentation Of Financial Statements [Line Items]

+ References

No definition available.

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Organization and Description of Business - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating income	$ 11,911	$ 14,531	$ 22,594	$ 27,752
WisdomTree Japan [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating income	$ 35	$ 1,125	465	$ 2,357
Impairment - Japan office lease			$ 572
Acquisition of ETFS Business [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Business Acquisition, Effective Date of Acquisition			Apr. 11, 2018