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Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Entity Registrant Name dei_EntityRegistrantName Ark ETF Trust
Entity Central Index Key dei_EntityCentralIndexKey 0001579982
Document Creation Date dei_DocumentCreationDate Sep. 16, 2014
Document Effective Date dei_DocumentEffectiveDate Sep. 17, 2014
Prospectus Date rr_ProspectusDate Sep. 30, 2014