Financial Instruments and Risk Management (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 24, 2011	Dec. 25, 2010	Sep. 24, 2011
Asset Fair Value Measurement Using Significant Unobservable Inputs (Level 3 ) [Roll Forward]
Beginning balance of over-the-counter options	$ 1,780	$ 1,509
Beginning balance realized during the period	(54)	0
Contracts purchased during the period	181	0
Change in the fair value of beginning balance	(508)	(101)
Ending balance of over-the-counter options	1,399	1,408
Liability Fair Value Measurement Using Significant Unobservable Inputs (Level 3 ) [Roll Forward]
Beginning balance of over-the-counter options	118	29
Beginning balance realized during the period	0	0
Contracts purchased during the period	0	0
Change in the fair value of beginning balance	(30)	(29)
Ending balance of over-the-counter options	88	0
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Unrealized Gains (Losses) Recognized in Income	(1,048)	(1,573)
Gains (Losses) Recognized in OCI (Effective Portion)	317	578
Gains (Losses) Reclassified from Accumulated OCI into Income (Effective Portion)	(695)	(723)
Weighted average maturity of outstanding commodity-related derivatives	3M		4M
Fair Value of 2020 Senior Notes	261,563		248,500
Commodity Option [Member] \| Not Designated as Hedging Instrument [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Unrealized Gains (Losses) Recognized in Income	538	33
Commodity Futures [Member] \| Not Designated as Hedging Instrument [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Unrealized Gains (Losses) Recognized in Income	(1,586)	(1,606)
Interest Rate Swap [Member] \| Derivatives in Cash Flow Hedging Relationships [Member] \| Designated as Hedging Instrument [Member] \| Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Recognized in OCI (Effective Portion)	317	578
Gains (Losses) Reclassified from Accumulated OCI into Income (Effective Portion)	(695)	(723)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	3,629		5,454
Fair value - liabilities	1,826		2,476
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	3,131		3,710
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	178		612
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	1,036		2,407
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	16		69
Not Designated as Hedging Instrument [Member] \| Commodity Futures [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	320		1,132
Not Designated as Hedging Instrument [Member] \| Commodity Futures [Member] \| Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	774		0
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	3,584		4,596
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	1,128		2,662
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	$ 2,456		$ 1,934

The average time remaining until maturity on the group of derivatives identified.

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- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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The increase (decrease) of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period. Such increase (decrease) may be comprised of changes in fair value (gains or losses) whether realized or unrealized that have been included in earnings, changed net asset value, or other comprehensive income (a separate component of shareholders' equity); purchases, sales, issuances, or settlements of assets; and net transfers in to or out of this category within the fair value hierarchy.

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Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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This element represents total gains or losses for the period (realized and unrealized), arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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The increase (decrease) of liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period. Such increase (decrease) may be comprised of changes in fair value (gains or losses) whether realized or unrealized that have been included in earnings, changed net asset value, or other comprehensive income (a separate component of shareholders' equity); purchases, sales, issuances, or settlements of assets; and net transfers in to or out of this category within the fair value hierarchy.

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Purchases that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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