Consolidated Statements of Comprehensive (Loss)/Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net (loss)/income	$ (10,425)	$ 36,633	$ 27,199
Other comprehensive income/(loss)
Change in unrealized gains/(losses) on available-for-sale debt securities, net of tax		477	(314)
Foreign currency translation adjustment	875	(301)	649
Reclassification of foreign currency translation adjustment to other losses, net, upon the liquidation of WisdomTree Japan Inc. (Note 1)	(397)
Other comprehensive income	478	176	335
Comprehensive (loss)/income	$ (9,947)	$ 36,809	$ 27,534

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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