v3.26.1
SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)
3 Months Ended
Jun. 30, 2026
Jun. 30, 2025
SIGNIFICANT ACCOUNTING POLICIES [Abstract]    
Sponsor's fee rate 0.19%  
Accrued Sponsor's fee $ 205,215  
Extraordinary or non-routine expenses $ 0 $ 0
Number of business days to transfer ownership of Bitcoin 1 day  
Franklin Bitcoin ETF [Member]    
SIGNIFICANT ACCOUNTING POLICIES [Abstract]    
Sponsor's fee rate 0.19%  
Accrued Sponsor's fee $ 205,215  
Extraordinary or non-routine expenses $ 0 $ 0
Number of business days to transfer ownership of Bitcoin 1 day  
Maximum [Member]    
SIGNIFICANT ACCOUNTING POLICIES [Abstract]    
Ordinary legal fees and expenses assumed by the sponsor $ 500,000  
Maximum [Member] | Franklin Bitcoin ETF [Member]    
SIGNIFICANT ACCOUNTING POLICIES [Abstract]    
Ordinary legal fees and expenses assumed by the sponsor $ 500,000