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.

No definition available.

+ Details

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Namespace Prefix:	senea_
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- 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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Period Type:	duration

- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

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Balance Type:	debit
Period Type:	instant

- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Details

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Basis of Presentation (detail) - USD ($)	3 Months Ended		6 Months Ended
Basis of Presentation (detail) - USD ($)	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014	Oct. 30, 2015
Sales Revenue [Line Items]
Net Sales	$ 313,202,000	$ 312,161,000	$ 539,460,000	$ 552,204,000
General Mills Operations Llc [Member]
Sales Revenue [Line Items]
Net Sales		$ 37,373,000	$ 32,765,000	$ 37,373,000
Gray & Company [Member]
Business Acquisition [Line Items]
Purchase Price					$ 24,500,000