Note 1 - Organization (Details Textual)			3 Months Ended
	Jun. 24, 2024	May 21, 2024 USD ($) $ / shares shares	Mar. 31, 2026 shares		Mar. 31, 2025 shares
Stock Issued During Period, Shares, New Issues (in shares)			74,680,000		39,960,000
Ether Purchased	3,031		564,146	[1]	302,532
Management and Service Fees, Base Rate	0.25%		0.25%
BlackRock Financial Management, Inc. [Member]
Stock Issued During Period, Shares, New Issues (in shares)		400,000
Stock Issued During Period, Value, New Issues | $		$ 10,000,000
Shares Issued, Price Per Share (in dollars per share) | $ / shares		$ 25

[1] Includes ether purchased in-kind for Shares issued of $621,312,812.