v3.26.1
Combined Statements of Changes in Net Assets - USD ($)
 3 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Net assets, beginning of period $ 429,340,099 $ 410,857,343
Operations:    
Net investment loss (205,215) (237,309)
Net realized gain (loss) on investment in bitcoin (396,857) 9,019,211
Net change in unrealized appreciation (depreciation) on investment in bitcoin (45,989,896) 119,518,907
Net increase (decrease) in net assets resulting from operations (46,591,968) 128,300,809
Increase (decrease) in net assets from capital Share transactions:    
Contributions for Shares issued [1] 5,799,402 55,501,643
Distributions for Shares redeemed (53,852,604) (35,230,580)
Net increase (decrease) in net assets from capital Share transactions (48,053,202) 20,271,063
Net assets, end of period 334,694,929 559,429,215
Franklin Bitcoin ETF [Member]    
Net assets, beginning of period 429,340,099 410,857,343
Operations:    
Net investment loss (205,215) (237,309)
Net realized gain (loss) on investment in bitcoin (396,857) 9,019,211
Net change in unrealized appreciation (depreciation) on investment in bitcoin (45,989,896) 119,518,907
Net increase (decrease) in net assets resulting from operations (46,591,968) 128,300,809
Increase (decrease) in net assets from capital Share transactions:    
Contributions for Shares issued [2] 5,799,402 55,501,643
Distributions for Shares redeemed (53,852,604) (35,230,580)
Net increase (decrease) in net assets from capital Share transactions (48,053,202) 20,271,063
Net assets, end of period $ 334,694,929 $ 559,429,215
[1] Dollar amount of balance represents the cumulative fair value of creation of Shares less the redemption of Shares, at the time of the specific creation or redemption.
[2] Dollar amount of balance represents the cumulative fair value of creation of Shares less the redemption of Shares, at the time of the specific creation or redemption.