Additional Term Loans

No definition available.

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Namespace Prefix:	eftr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Extended cut off date before which the interest on term loan paid.

+ References

No definition available.

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- Definition

Number of days within which a portion of term loan will be available subject to achievement of milestone.

+ References

No definition available.

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- Definition

Number of tranches.

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No definition available.

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- Definition

Prepayment fee as a percentage of the outstanding principal.

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No definition available.

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- Definition

Term loan final payment as a percentage of the amount funded.

+ References

No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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No definition available.

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Identification of the lender and information about a contractual promise to repay a short-term or long-term obligation, which includes borrowings under lines of credit, notes payable, commercial paper, bonds payable, debentures, and other contractual obligations for payment. This may include rationale for entering into the arrangement, significant terms of the arrangement, which may include amount, repayment terms, priority, collateral required, debt covenants, borrowing capacity, call features, participation rights, conversion provisions, sinking-fund requirements, voting rights, basis for conversion if convertible and remarketing provisions. The description may be provided for individual debt instruments, rational groupings of debt instruments, or by debt in total.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

Date the credit facility first became available, in YYYY-MM-DD format.

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- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Term Loans - Additional Information (Detail) $ / shares in Units, $ in Thousands		3 Months Ended
	Feb. 22, 2022 USD ($)	Mar. 31, 2023 USD ($) $ / shares shares	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($) Tranche	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Outstanding principal, Term loans		$ 19,137
Extended cut off date before which the interest on term loan shall be paid	Mar. 01, 2024
Long term debt net of unamortized debt discounts		$ 20,000
Loan and Security Agreement [Member] \| Less Than One Year From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal				3.00%
Loan and Security Agreement [Member] \| Greater Than One Year And Less Than Two Years From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal				2.00%
Loan and Security Agreement [Member] \| Later Than Two Years And Not Later Than Three Years From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal				1.00%
Loan and Security Agreement [Member] \| Later Than Three Years From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Prepayment fee as a percentage of the outstanding principal				0.00%
Loan and Security Agreement [Member] \| Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Number of tranches \| Tranche				2
Debt instrument, face amount				$ 30,000
Number of days within which a portion of term loan will be available subject to achievement of milestone	45 days
Long term debt variable interest rate percentage				7.70%
Loan and Security Agreement [Member] \| Prime Rate [Member] \| Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate spread				4.45%
Loan and Security Agreement [Member] \| Warrants To Purchase Series C Redeemable Convertible Stock \| Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Exercise price of warrants \| $ / shares		$ 5.33
Number of shares subject to each warrant \| shares		37,575
Loan and Security Agreement [Member] \| Common Stock [Member] \| Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Common stock up on conversion \| shares		17,575
Loan and Security Agreement [Member] \| Debt Instrument, Term Loan A [Member] \| Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Debt Instrument, Discount		$ 1,600
Outstanding principal, Term loans		20,000		$ 20,000	$ 20,000
Amortization of debt discount		700	$ 500
Issuance of term loans, net of issuance costs				$ 12,500
Extended maturity of Term A Loans, Description	In connection with the amendment, the maturity of the Term A Loans was extended from March 18, 2026 to February 1, 2027.
Term loan final payment as a percentage of the amount funded				5.50%
Long term debt net of unamortized debt discounts		$ 19,100			$ 19,100
Loan and Security Agreement [Member] \| Debt Instrument, Term Loan B [Member]
Debt Instrument [Line Items]
Additional Term Loans	$ 10,000
Loan and Security Agreement [Member] \| Debt Instrument, Term Loan B [Member] \| Less Than One Year From The Date Of Loan Agreement [Member]
Debt Instrument [Line Items]
Loan initiation date	Jun. 30, 2023
Loan and Security Agreement [Member] \| Debt Instrument, Term Loan B [Member] \| Oxford Finance LLC [Member]
Debt Instrument [Line Items]
Debt instrument, face amount				$ 10,000
Issuance of term loans, net of issuance costs				$ 7,400