This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
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The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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This element represents disclosure of the amount of gain which has been deferred as the result of the sale of a business or operating assets to a highly leveraged entity which deferred gain has been reflected in the accompanying statement of financial position as reduction from the related asset.

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No definition available.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The number of units of other ownership interests issued in a limited partnership or master limited partnership. Does not include limited or general partners' ownership interests.

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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

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No definition available.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, AVAILABLE FOR SALE SECURITIES (Details) - USD ($) shares in Thousands		12 Months Ended
	Sep. 29, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities		$ 55,789,000	$ 59,475,000
Unrealized gain		7,200,000	10,800,000
Unrealized gain, after tax		4,200,000	6,400,000
Carrying amount of investment		141,148,000	132,002,000
Proceeds from sale of available for sale securities		$ 0	$ 0
Common Units
Schedule of Available-for-sale Securities [Line Items]
Ownership interest exchanged (in shares)	1,840
Iroquois
Schedule of Available-for-sale Securities [Line Items]
Ownership interest, percent	5.53%			5.53%
Carrying amount of investment	$ 21,500,000
Dominion
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities	46,100,000
Deferred gain	$ 24,600,000