v3.26.1
Note 10 - Investment Valuation - Valuation of the Trust's Investments by the Fair Value Hierarchy (Details)
Jun. 30, 2026
USD ($)
Options Written $ (165,163) [1]
BlackRock Cash Funds: Treasury, SL Agency Shares [Member]  
Investment, fair value 20,094
iShares Bitcoin Trust ETF [Member]  
Investment, fair value 14,231,678
Fair Value, Inputs, Level 1 [Member]  
Options Written (165,163)
Fair Value, Inputs, Level 1 [Member] | BlackRock Cash Funds: Treasury, SL Agency Shares [Member]  
Investment, fair value 20,094
Fair Value, Inputs, Level 1 [Member] | iShares Bitcoin Trust ETF [Member]  
Investment, fair value 14,231,678
Fair Value, Inputs, Level 2 [Member]  
Options Written 0
Fair Value, Inputs, Level 2 [Member] | BlackRock Cash Funds: Treasury, SL Agency Shares [Member]  
Investment, fair value 0
Fair Value, Inputs, Level 2 [Member] | iShares Bitcoin Trust ETF [Member]  
Investment, fair value 0
Fair Value, Inputs, Level 3 [Member]  
Options Written 0
Fair Value, Inputs, Level 3 [Member] | BlackRock Cash Funds: Treasury, SL Agency Shares [Member]  
Investment, fair value 0
Fair Value, Inputs, Level 3 [Member] | iShares Bitcoin Trust ETF [Member]  
Investment, fair value 0
Bitcoin [Member]  
Investment, fair value 28,595,505
Bitcoin [Member] | Fair Value, Inputs, Level 1 [Member]  
Investment, fair value 28,595,505
Bitcoin [Member] | Fair Value, Inputs, Level 2 [Member]  
Investment, fair value 0
Bitcoin [Member] | Fair Value, Inputs, Level 3 [Member]  
Investment, fair value $ 0
[1] Premiums received $430,939.