Quarterly report pursuant to Section 13 or 15(d)

Business - Summary of entities in control (Detail)

v3.21.1
Business - Summary of entities in control (Detail)
 9 Months Ended
Mar. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation DE    
Benitec Biopharma Proprietary Limited ("BBL") [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation C3    
Equity method investment, ownership percentage   100.00%  
Benitec Australia Proprietary Limited [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation C3    
Equity method investment, ownership percentage   100.00% 100.00%
Benitec Limited [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation X0    
Equity method investment, ownership percentage   100.00% 100.00%
Benitec, Inc. [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation X1    
Equity method investment, ownership percentage   100.00% 100.00%
Benitec LLC [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation X1    
Equity method investment, ownership percentage   100.00% 100.00%
RNAi Therapeutics, Inc. [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation X1    
Equity method investment, ownership percentage   100.00% 100.00%
Tacere Therapeutics, Inc. [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation X1    
Equity method investment, ownership percentage   100.00% 100.00%
Benitec Biopharma Proprietary Limited [Member]      
Schedule Of Entities In Control [Line Items]      
Principal place of business/country of incorporation C3