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Namespace Prefix:	senea_
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Balance Type:	na
Period Type:	duration

The general payment term for accounts receivable related to the sale of the reporting entity's vegetable and fruit products.

No definition available.

Name:	senea_AccountsReceivableVegetableAndFruitProductsSoldStandardPaymentTerm
Namespace Prefix:	senea_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the minimum EBITDA associated with financial covenants under debt agreements.

No definition available.

Name:	senea_DebtAgreementsFinancialCovenantsMinimumEBITDA
Namespace Prefix:	senea_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents maximum amount of available line of credit that requires minimum fixed charge coverage ratio.

No definition available.

Name:	senea_DebtInstrumentCovenantMaximumAmountForAvailableLineOfCreditThatRequiresMinimumFixedChargeCoverageRatio
Namespace Prefix:	senea_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Represents the maximum percentage of commitments for available line of credit that requires minimum fixed charge coverage ratio.

No definition available.

Name:	senea_DebtInstrumentCovenantMaximumPercentageOfCommitmentsForAvailableLineOfCreditThatRequiresMinimumFixedChargeCoverageRatio
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Maximum borrowing capacity under the credit facility during the reporting entity's nonproduction period without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

No definition available.

Name:	senea_LineOfCreditFacilityMaximumBorrowingCapacityDuringNonproductionPeriod
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Maximum borrowing capacity under the credit facility during the reporting entity's production period without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

No definition available.

Name:	senea_LineOfCreditFacilityMaximumBorrowingCapacityDuringProductionPeriod
Namespace Prefix:	senea_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Increase amount of maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

No definition available.

Name:	senea_LineOfCreditFacilityMaximumBorrowingCapacityIncrease
Namespace Prefix:	senea_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The carrying amount, as of the date of the latest financial statement presented, of fixed assets owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

No definition available.

Name:	senea_PledgedAssetsNotSeparatelyReportedFixedAssets
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Cash inflow from patronage distributions.

No definition available.

Name:	senea_ProceedsFromPatronageDistributions
Namespace Prefix:	senea_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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Data Type:	dtr-types:percentItemType
Balance Type:	na
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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Name:	us-gaap_DebtInstrumentMaturityDate
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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

Amount of the required periodic payments applied to principal.

Name:	us-gaap_DebtInstrumentPeriodicPaymentPrincipal
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Balance Type:	debit
Period Type:	duration

Amount, after accumulated amortization, of debt discount.

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Indicates type of variable interest rate on debt instrument.

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Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	duration

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

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

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Name:	us-gaap_LongTermDebt
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Period Type:	instant

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

Name:	us-gaap_NotesPayable
Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

Amount of dividends that can be declared or paid without approval of regulatory agency.

No definition available.

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Namespace Prefix:	us-gaap_
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Name:	us-gaap_LongtermDebtTypeAxis=senea_AmendedTermLoanA2Member
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