XML 53 R42.htm IDEA: XBRL DOCUMENT
v3.19.1

Common Stock Warrants (Details Narrative) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 8 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Nov. 15, 2018 USD ($) shares | Jun. 30, 2017 USD ($) $ / shares shares | May 31, 2017 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares | Dec. 31, 2017 USD ($) $ / shares | Dec. 31, 2018 USD ($) $ / shares shares | Nov. 30, 2018 $ / shares shares
Warrants issued to purchase common stock | shares |  |  |  |  |  | 1,718,184 |
Warrants exercise price | $ / shares |  |  |  |  |  | $ 3.04 |
Warrants, fair value | $ |  |  |  | $ 41 |  | $ 2,583 |
Expected term |  |  |  |  |  | 6 years 3 months 19 days |
Volatility rate |  |  |  | 85.00% |  | 85.00% |
Expected dividends rate |  |  |  | 0.00% |  | 0.00% |
Warrant [Member] |  |  |  |  |  |  |
Warrants issued to purchase common stock | shares |  |  |  |  |  |  | 414,000
Warrants exercise price | $ / shares |  |  |  |  |  |  | $ 7.50
Warrant [Member] | Consultant and Placement Agent [Member] |  |  |  |  |  |  |
Weighted average exercise price of warrants | $ / shares |  |  |  | $ 1.56 | $ 1.56 | $ 3.04 |
Redeemable Convertible Preferred Stock - Series A [Member] |  |  |  |  |  |  |
Warrants, fair value | $ | $ 3,103 |  |  |  | $ 520 |  |
Expected term | 5 years |  |  |  |  |  |
Volatility rate | 85.00% |  |  |  |  |  |
Risk-free interest rate | 2.90% |  |  |  |  |  |
Preferred stock, issuance costs | $ |  | $ 479 |  |  |  |  |
Common stock issued upon warrants conversion basis |  | 1.333 |  |  |  |  |
Common stock issued upon warrants conversion basis, description |  | Prior to the Company's IPO in November 2018, the number of common shares issuable upon the exercise of this warrant was not fixed as it could vary by a factor of 1.000 to 1.333 common shares per warrant share in accordance with the IPO price, and the Company considered the warrant to be a derivative instrument (see Note 4). |  |  |  |  |
Increase in fair value of warrant | $ | $ 2,583 |  |  |  | $ 41 |  |
Placement Agent [Member] | Redeemable Convertible Preferred Stock - Series A [Member] |  |  |  |  |  |  |
Warrants issued to purchase common stock | shares |  | 649,409 |  |  |  |  |
Warrants exercise price | $ / shares |  | $ 3.00 |  |  |  |  |
Warrants conversion, description |  | The warrant adjusted to entitle the holder to purchase shares of common stock equal to 10.0% of the shares of common stock issuable upon conversion of the Series A Preferred (excluding 191,000 shares of Series A Preferred that were purchased by insiders) and the exercise price would adjust to the conversion price of the Series A Preferred. This warrant vested at issuance in June 2017. |  |  |  |  |
Common stock issuable upon conversion of preferred stock | shares |  | 191,000 |  |  |  |  |
Initial Public Offering [Member] | Redeemable Convertible Preferred Stock - Series A [Member] |  |  |  |  |  |  |
Number of shares issuable upon exercise warrants | shares | 704,184 |  |  |  |  |  |
General and Administrative Expense [Member] |  |  |  |  |  |  |
Consulting warrants expense | $ |  |  | $ 121 |  |  |  |
Business Strategy and Intellectual Property Advisory Services [Member] |  |  |  |  |  |  |
Warrants issued to purchase common stock | shares |  |  | 600,000 |  |  |  |
Warrants exercise price | $ / shares |  |  | $ 0.01 |  |  |  |
Warrants expiration term |  |  | 5 years |  |  |  |
Warrants, fair value | $ |  |  | $ 121 |  |  |  |
Expected term |  |  | 5 years |  |  |  |
Volatility rate |  |  | 85.00% |  |  |  |
Risk-free interest rate |  |  | 1.80% |  |  |  |
Expected dividends rate |  |  | 0.00% |  |  |  |

X
- Definition Class of warrant or right weighted average exercise price of warrants or rights. + References No definition available. + Details
Name: | ETON_ClassOfWarrantOrRightWeightedAverageExercisePriceOfWarrantsOrRights
Namespace Prefix: | ETON_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Common stock issued upon warrants conversion basis. + References No definition available. + Details
Name: | ETON_CommonStockIssuedUponWarrantsConversionBasis
Namespace Prefix: | ETON_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Definition Common stock issued upon warrants conversion basis, description. + References No definition available. + Details
Name: | ETON_CommonStockIssuedUponWarrantsConversionBasisDescription
Namespace Prefix: | ETON_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Conversion of warrants, description. + References No definition available. + Details
Name: | ETON_ConversionOfWarrantsDescription
Namespace Prefix: | ETON_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Increase in fair value of warrant. + References No definition available. + Details
Name: | ETON_IncreaseInFairvalueOfWarrant
Namespace Prefix: | ETON_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of shares issuable upon exercise warrants. + References No definition available. + Details
Name: | ETON_NumberOfSharesIssuableUponExerciseWarrants
Namespace Prefix: | ETON_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Preferred stock, issuance costs. + References No definition available. + Details
Name: | ETON_PreferredStockIssuanceCosts
Namespace Prefix: | ETON_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Warrants expense for consultation. + References No definition available. + Details
Name: | ETON_WarrantsExpenseForConsultation
Namespace Prefix: | ETON_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of new shares issued in the conversion of stock 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
Name: | us-gaap_ConversionOfStockSharesIssued1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expense (income) related to adjustment to fair value of warrant liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section 25 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=109262497&loc=d3e20148-110875 + Details
Name: | us-gaap_FairValueAdjustmentOfWarrants
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 + Details
Name: | us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
Name: | us-gaap_WarrantsAndRightsOutstandingTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_WarrantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=ETON_ConsultantAndPlacementAgentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=ETON_RedeemableConvertiblePreferredStockSeriesAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=us-gaap_IPOMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=us-gaap_GeneralAndAdministrativeExpenseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=ETON_BusinessStrategyAndIntellectualPropertyAdvisoryServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |