Combined Statements of Changes in Net Assets - USD ($)		3 Months Ended		9 Months Ended
		Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024
Net assets, beginning of period		$ 661,050,465	$ 452,290,641	$ 410,857,343	$ 341,901,105
Net investment loss		(278,172)	(295,795)	(812,154)	(419,080)
Net realized gain (loss) on investment in bitcoin		6,465,881	2,814,719	22,776,065	1,657,725
Net change in unrealized appreciation (depreciation) on investment in bitcoin		(163,300,788)	211,365,660	(22,665,827)	179,027,692
Net increase (decrease) in net assets resulting from operations		(157,113,079)	213,884,584	(701,916)	180,266,337
Capital Share Transactions:
Contributions for Shares issued	[1]	28,966,925	69,053,710	177,354,133	278,780,084
Distributions for Shares redeemed		(32,029,773)	(23,658,861)	(86,635,022)	(89,377,452)
Net increase (decrease) in net assets from capital share transactions		(3,062,848)	45,394,849	90,719,111	189,402,632
Net assets, end of period		500,874,538	711,570,074	500,874,538	711,570,074
Franklin Bitcoin ETF [Member]
Net assets, beginning of period		661,050,465	452,290,641	410,857,343	341,901,105
Net investment loss		(278,172)	(295,795)	(812,154)	(419,080)
Net realized gain (loss) on investment in bitcoin		6,465,881	2,814,719	22,776,065	1,657,725
Net change in unrealized appreciation (depreciation) on investment in bitcoin		(163,300,788)	211,365,660	(22,665,827)	179,027,692
Net increase (decrease) in net assets resulting from operations		(157,113,079)	213,884,584	(701,916)	180,266,337
Capital Share Transactions:
Contributions for Shares issued	[2]	28,966,925	69,053,710	177,354,133	278,780,084
Distributions for Shares redeemed		(32,029,773)	(23,658,861)	(86,635,022)	(89,377,452)
Net increase (decrease) in net assets from capital share transactions		(3,062,848)	45,394,849	90,719,111	189,402,632
Net assets, end of period		$ 500,874,538	$ 711,570,074	$ 500,874,538	$ 711,570,074

[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.