Organization	6 Months Ended
Jun. 30, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization	1. Organization Grayscale Ethereum Trust (ETH) (the “Trust”) is a Delaware Statutory Trust that was formed on December 13, 2017 and commenced operations on December 14, 2017. In general, the Trust holds Ethereum (“ETH”) and, from time to time, issues common units of fractional undivided beneficial interest (“Shares”) (in minimum baskets of 100 Shares, referred to as “Baskets”) in exchange for ETH. The redemption of Shares is not currently contemplated and the Trust does not currently operate a redemption program. Subject to receipt of regulatory approval and approval by the Sponsor in its sole discretion, the Trust may in the future operate a redemption program. The Trust currently has no intention of seeking regulatory approval to operate an ongoing redemption program. The Trust’s investment objective is for the value of the Shares (based on ETH per Share) to reflect the value of ETH held by the Trust, less the Trust’s expenses and other liabilities. The Trust may also receive Incidental Rights and/or IR Virtual Currency as a result of the Trust’s investment in ETH, in accordance with the terms of the Trust Agreement. Incidental Rights are rights to claim, or otherwise establish dominion and control over, any virtual currency or other asset or right, which rights are incident to the Trust’s ownership of ETH and arise without any action of the Trust, or of the Sponsor or Trustee on behalf of the Trust; IR Virtual Currency is any virtual currency tokens, or other asset or right, received by the Trust through the exercise (subject to the applicable provisions of the Trust Agreement) of any Incidental Right. Grayscale Investments LLC (“Grayscale” or the “Sponsor”) acts as the Sponsor of the Trust and is a wholly owned subsidiary of Digital Currency Group, Inc. (“DCG”). The Sponsor is responsible for the day-to-day administration of the Trust pursuant to the provisions of the Trust Agreement. Grayscale is responsible for preparing and providing annual and quarterly reports on behalf of the Trust to investors and is also responsible for selecting and monitoring the Trust’s service providers. As partial consideration for the Sponsor’s services, the Trust pays Grayscale a Sponsor’s Fee as discussed in Note 6. The Sponsor also acts as the sponsor and manager of other investment products including Grayscale Bitcoin Trust (BTC) (OTCQX: GBTC), Grayscale Basic Attention Token Trust (BAT), Grayscale Bitcoin Cash Trust (BCH) (OTCQX: BCHG), Grayscale Chainlink Trust (LINK), Grayscale Decentraland Trust (MANA), Grayscale Ethereum Classic Trust (ETC) (OTCQX: ETCG), Grayscale Filecoin Trust (FIL), Grayscale Horizen Trust (ZEN), Grayscale Litecoin Trust (LTC) (OTCQX: LTCN), Grayscale Livepeer Trust (LPT), Grayscale Stellar Lumens Trust (XLM), Grayscale Zcash Trust (ZEC), Grayscale Decentralized Finance Fund LLC (DeFi), and Grayscale Digital Large Cap Fund LLC (OTCQX: GDLC), each of which is an affiliate of the Trust. The following investment products sponsored or managed by the Sponsor are also SEC reporting companies with their shares registered pursuant to Section 12(g) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”): Grayscale Bitcoin Trust (BTC) and Grayscale Digital Large Cap Fund LLC (GDLC). Authorized Participants of the Trust are the only entities who may place orders to create or, if permitted, redeem Baskets. Genesis Global Trading, Inc. (“Genesis” or the “Authorized Participant”), a registered broker-dealer and wholly owned subsidiary of DCG, is the only Authorized Participant and is party to a participant agreement with the Sponsor and the Trust. Additional Authorized Participants may be added at any time, subject to the discretion of the Sponsor. The custodian of the Trust is Coinbase Custody Trust Company, LLC (the “Custodian”), a third-party service provider. The Custodian is responsible for safeguarding the ETH, Incidental Rights, and IR Virtual Currency held by the Trust, and holding the private key(s) that provide access to the Trust’s digital wallets and vaults. The Custodian Agreement is for an initial term of three years. The transfer agent for the Trust (the “Transfer Agent”) is Continental Stock Transfer & Trust Company. The responsibilities of the Transfer Agent are to maintain creations, redemptions, transfers, and distributions of the Trust’s Shares which are primarily held in book-entry form. On May 23, 2019, the Trust received notice that its Shares were qualified for public trading on the OTCQX U.S. Marketplace of the OTC Markets Group Inc. (“OTCQX”). The Trust’s trading symbol on OTCQX is “ETHE” and the CUSIP number for its Shares is 389638107. On December 17, 2020, the Trust completed a 9-for-1 Share Split of the Trust’s issued and outstanding Shares. Each beneficial owner of a Share (a “shareholder”) of record as of the close of business on December 14, 2020 received eight additional Shares of the Trust for each Share held. The number of outstanding Shares and per-Share amounts disclosed for all periods presented have been retroactively adjusted to reflect the effects of the Share Split.

Organization

6 Months Ended

Jun. 30, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

1. Organization

Grayscale Ethereum Trust (ETH) (the “Trust”) is a Delaware Statutory Trust that was formed on December 13, 2017 and commenced operations on December 14, 2017. In general, the Trust holds Ethereum (“ETH”) and, from time to time, issues common units of fractional undivided beneficial interest (“Shares”) (in minimum baskets of 100 Shares, referred to as “Baskets”) in exchange for ETH. The redemption of Shares is not currently contemplated and the Trust does not currently operate a redemption program. Subject to receipt of regulatory approval and approval by the Sponsor in its sole discretion, the Trust may in the future operate a redemption program. The Trust currently has no intention of seeking regulatory approval to operate an ongoing redemption program. The Trust’s investment objective is for the value of the Shares (based on ETH per Share) to reflect the value of ETH held by the Trust, less the Trust’s expenses and other liabilities. The Trust may also receive Incidental Rights and/or IR Virtual Currency as a result of the Trust’s investment in ETH, in accordance with the terms of the Trust Agreement.

Incidental Rights are rights to claim, or otherwise establish dominion and control over, any virtual currency or other asset or right, which rights are incident to the Trust’s ownership of ETH and arise without any action of the Trust, or of the Sponsor or Trustee on behalf of the Trust; IR Virtual Currency is any virtual currency tokens, or other asset or right, received by the Trust through the exercise (subject to the applicable provisions of the Trust Agreement) of any Incidental Right.

Grayscale Investments LLC (“Grayscale” or the “Sponsor”) acts as the Sponsor of the Trust and is a wholly owned subsidiary of Digital Currency Group, Inc. (“DCG”). The Sponsor is responsible for the day-to-day administration of the Trust pursuant to the provisions of the Trust Agreement. Grayscale is responsible for preparing and providing annual and quarterly reports on behalf of the Trust to investors and is also responsible for selecting and monitoring the Trust’s service providers. As partial consideration for the Sponsor’s services, the Trust pays Grayscale a Sponsor’s Fee as discussed in Note 6. The Sponsor also acts as the sponsor and manager of other investment products including Grayscale Bitcoin Trust (BTC) (OTCQX: GBTC), Grayscale Basic Attention Token Trust (BAT), Grayscale Bitcoin Cash Trust (BCH) (OTCQX: BCHG), Grayscale Chainlink Trust (LINK), Grayscale Decentraland Trust (MANA), Grayscale Ethereum Classic Trust (ETC) (OTCQX: ETCG), Grayscale Filecoin Trust (FIL), Grayscale Horizen Trust (ZEN), Grayscale Litecoin Trust (LTC) (OTCQX: LTCN), Grayscale Livepeer Trust (LPT), Grayscale Stellar Lumens Trust (XLM), Grayscale Zcash Trust (ZEC), Grayscale Decentralized Finance Fund LLC (DeFi), and Grayscale Digital Large Cap Fund LLC (OTCQX: GDLC), each of which is an affiliate of the Trust. The following investment products sponsored or managed by the Sponsor are also SEC reporting companies with their shares registered pursuant to Section 12(g) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”): Grayscale Bitcoin Trust (BTC) and Grayscale Digital Large Cap Fund LLC (GDLC).

Authorized Participants of the Trust are the only entities who may place orders to create or, if permitted, redeem Baskets. Genesis Global Trading, Inc. (“Genesis” or the “Authorized Participant”), a registered broker-dealer and wholly owned subsidiary of DCG, is the only Authorized Participant and is party to a participant agreement with the Sponsor and the Trust. Additional Authorized Participants may be added at any time, subject to the discretion of the Sponsor.

The custodian of the Trust is Coinbase Custody Trust Company, LLC (the “Custodian”), a third-party service provider. The Custodian is responsible for safeguarding the ETH, Incidental Rights, and IR Virtual Currency held by the Trust, and holding the private key(s) that provide access to the Trust’s digital wallets and vaults. The Custodian Agreement is for an initial term of three years.

The transfer agent for the Trust (the “Transfer Agent”) is Continental Stock Transfer & Trust Company. The responsibilities of the Transfer Agent are to maintain creations, redemptions, transfers, and distributions of the Trust’s Shares which are primarily held in book-entry form.

On May 23, 2019, the Trust received notice that its Shares were qualified for public trading on the OTCQX U.S. Marketplace of the OTC Markets Group Inc. (“OTCQX”). The Trust’s trading symbol on OTCQX is “ETHE” and the CUSIP number for its Shares is 389638107.

On December 17, 2020, the Trust completed a 9-for-1 Share Split of the Trust’s issued and outstanding Shares. Each beneficial owner of a Share (a “shareholder”) of record as of the close of business on December 14, 2020 received eight additional Shares of the Trust for each Share held. The number of outstanding Shares and per-Share amounts disclosed for all periods presented have been retroactively adjusted to reflect the effects of the Share Split.