Credit Facility - Additional Information (Detail) - Senior Secured Revolving Credit Facility [Member] - USD ($) $ in Thousands	Mar. 05, 2020	Mar. 26, 2020
Debt Instrument [Line Items]
Revolving loan commitment and letter of credit sub facility	$ 117,500	$ 117,500
Available credit under the Credit Facility		76,150
Revolver availability plus unrestricted cash	$ 15,000
Revolving credit facility covenants	revolver availability plus unrestricted cash must be equal to or greater than $15,000 and the pro forma fixed charge coverage ratio must be equal to or greater than 1.00:1.00
Revolver availability plus unrestricted cash after acquisition	$ 20,000
Outstanding letters of credit		3,175
Revolving credit facility borrowings		$ 38,175
Aggregate amount of dividends and distributions permitted	75,000
Excess availability required under the credit facility	30,000
Revolver availability plus unrestricted cash after proposed investments	20,000
Increased threshold exclusion of dividends and distributions	40,000
Incremental Revolver [Member]
Debt Instrument [Line Items]
Revolving loan commitment and letter of credit sub facility	50,000
Purchase Money and Capital Lease Basket [Member]
Debt Instrument [Line Items]
Revolving loan commitment and letter of credit sub facility	10,000
Unsecured Subordinated Indebtedness [Member]
Debt Instrument [Line Items]
Revolving loan commitment and letter of credit sub facility	10,000
Additional Unsecured Subordinated Indebtedness [Member]
Debt Instrument [Line Items]
Revolving loan commitment and letter of credit sub facility	$ 20,000

Amount of excess availability required under the credit facility after the declaration of dividends.

No definition available.

Name:	jbss_ExcessCreditAvailability
Namespace Prefix:	jbss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Increased threshold exclusion of dividends and distributions.

+ References

No definition available.

+ Details

Name:	jbss_IncreasedThresholdExclusionOfDividendsAndDistributions
Namespace Prefix:	jbss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of credit covenant minimum availability of revolver and unrestricted cash.

+ References

No definition available.

+ Details

Name:	jbss_LineOfCreditCovenantMinimumAvailabilityOfRevolverAndUnrestrictedCash
Namespace Prefix:	jbss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of credit covenant minimum availability of revolver and unrestricted cash after acquisition.

+ References

No definition available.

+ Details

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Namespace Prefix:	jbss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of credit covenant minimum availability of revolver and unrestricted cash after proposed investments.

+ References

No definition available.

+ Details

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Namespace Prefix:	jbss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ References

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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

- Definition

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.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ 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.(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=jbss_UnsecuredSubordinatedIndebtednessMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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