XML 39 R27.htm IDEA: XBRL DOCUMENT
v3.21.2

Organization and Basis of Presentation. (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Organization and Basis of Presentation. (Details) [Line Items] |  |  |  |  |
Accounts receivable balance | $ 61,501,000 |  | $ 61,501,000 |  | $ 35,839,000
Allowance for doubtful accounts | 363,000 |  | 363,000 |  | $ 260,000
Bad debt expense |  |  | $ 143,000 | $ 1,000 |
Combined Production Capacity, Description |  |  | The Company has a combined production capacity of 410 million gallons per year, markets, on an annualized basis, over 500 million gallons of alcohols, and produces, on an annualized basis, nearly 1.5 million tons of essential ingredients on a dry matter basis, such as dried yeast, corn gluten meal, corn gluten feed, and distillers grains and liquid feed used in commercial animal feed and pet foods. |  |
Operating annual production, Description |  |  | the Company was operating at approximately 71% of its 410 million gallon annual production capacity. |  |
Debt [Member] |  |  |  |  |
Organization and Basis of Presentation. (Details) [Line Items] |  |  |  |  |
Bad debt expense | $ 52,000 | $ 18,000 | $ 143,000 | $ 1,000 |

X
- References No definition available. + Details
Name: | alto_CombinedProductionCapacityDescription
Namespace Prefix: | alto_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Operating annual production + References No definition available. + Details
Name: | alto_OperatingAnnualProductionDescription
Namespace Prefix: | alto_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | alto_OrganizationandBasisofPresentationDetailsLineItems
Namespace Prefix: | alto_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4531-111522 + Details
Name: | us-gaap_AccountsReceivableGrossCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The fair value, as of the date of each statement of financial position presented, of finance receivables which are owned but transferred to serve as collateral for the payment of the related debt obligation, and that are reclassified and separately reported in the statement of financial position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 + Details
Name: | us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(5)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 + Details
Name: | us-gaap_ProvisionForDoubtfulAccounts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentAxis=us-gaap_DebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |