Name:	seb_ScheduleOfIncomeLossFromEquityMethodInvestmentsBySegmentTextBlock
Namespace Prefix:	seb_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of investments in and advances to affiliates by segment.

No definition available.

Name:	seb_ScheduleOfInvestmentInAndAdvancesToAffiliatesBySegmentTextBlock
Namespace Prefix:	seb_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of pro forma results of operations for a material business acquisition or series of individually immaterial business acquisitions that are material in the aggregate.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

Name:	us-gaap_BusinessAcquisitionProFormaInformationTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of all significant reconciling items in the reconciliation of total assets from reportable segments to the entity's consolidated assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8906-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8924-108599

Name:	us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the reconciliation of profit (loss) from reportable segments to the consolidated income (loss) before income tax expense (benefit) and discontinued operations. Includes, but is not limited to, reconciliation after income tax if income tax is allocated to the reportable segment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8906-108599

Name:	us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of a material business combination completed during the period, including background, timing, and recognized assets and liabilities. This table does not include leveraged buyouts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1486-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

Name:	us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of entity-wide revenues from external customers for each product or service or each group of similar products or services if the information is not provided as part of the reportable operating segment information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9031-108599

Name:	us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of quarterly financial data. Includes, but is not limited to, financial information for fiscal quarters, cumulative effect of a change in accounting principle and earnings per share data.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)-(j)
-URI http://asc.fasb.org/extlink&oid=68076893&loc=d3e1280-108306

Name:	us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=seb_ButterballLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_BusinessAcquisitionAxis=seb_TexasFarmLLCAndChristensenFarmsAndFeedlotsIncAndChristensenFarmsMidwestLlcAssetsAndHogInventoryAndSowFarmMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_BusinessAcquisitionAxis=seb_TexasFarmLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: