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Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)
Apr. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Jan. 01, 2016
Indefinite-lived Intangible Assets [Line Items]          
Goodwill, impairment loss $ 0        
Intangible asset related to its customary advisory agreement   $ 9,953,000   $ 9,953,000  
GreenHaven Commodity Services, LLC [Member]          
Indefinite-lived Intangible Assets [Line Items]          
Intangible asset related to its customary advisory agreement   $ 9,953,000 $ 9,953,000   $ 9,953,000