SIGNIFICANT ACCOUNTING POLICIES - Summary of changes in shares (Details) - Franklin Bitcoin ETF [Member] - USD ($)		3 Months Ended		9 Months Ended
		Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024
SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Beginning Balance (in Shares)		10,000,000	12,250,000	8,550,000	8,350,000
Beginning Balance	[1]	$ 334,210,567	$ 424,631,725	$ 240,428,608	$ 280,623,942
Creation of Shares (in Shares)		500,000	1,500,000	2,950,000	7,350,000
Creation of Shares	[1]	$ 28,966,925	$ 69,053,710	$ 177,354,133	$ 278,780,084
Redemption of Shares (in Shares)		(600,000)	(600,000)	(1,600,000)	(2,550,000)
Redemption of Shares	[1]	$ (32,029,773)	$ (23,658,861)	$ (86,635,022)	$ (89,377,452)
Ending Balance (in Shares)		9,900,000	13,150,000	9,900,000	13,150,000
Ending Balance	[1]	$ 331,147,719	$ 470,026,574	$ 331,147,719	$ 470,026,574

[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.