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

No definition available.

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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- Definition

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.

+ References

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- Definition

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

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph b

-Clause 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

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- Definition

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.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (b)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

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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.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

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- Definition

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1), c(2), c(3)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

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- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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.

+ References

+ Details

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- Definition

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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- Definition

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.

+ References

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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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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Financial Instruments and Risk Management (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 24, 2012	Mar. 26, 2011	Mar. 24, 2012	Mar. 26, 2011	Sep. 24, 2011
Asset Fair Value Measurement Using Significant Unobservable Inputs (Level 3 ) [Roll Forward]
Opening balance of over-the-counter options			$ 1,780	$ 1,509
Beginning balance realized during the period			(398)	(833)
Contracts purchased during the period			330	475
Change in the fair value of beginning balance			(770)	(41)
Closing balance of over-the-counter options	942	1,110	942	1,110
Liability Fair Value Measurement Using Significant Unobservable Inputs (Level 3 ) [Roll Forward]
Opening balance of over-the-counter options			118	29
Beginning balance realized during the period			0	(11)
Contracts purchased during the period			0	0
Change in the fair value of beginning balance			(97)	(18)
Closing balance of over-the-counter options	21	0	21	0
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Unrealized Gains (Losses) Recognized in Income	0	4,123	(1,048)	2,550
Gains (Losses) Recognized in OCI (Effective Portion)	(695)	(352)	(378)	226
Gains (Losses) Reclassified from Accumulated OCI into Income (Effective Portion)	(642)	(704)	(1,338)	(1,428)
Weighted average maturity of outstanding commodity-related derivatives	5M		5M		4M
Fair Value of 2020 Senior Notes	270,000		270,000		248,500
Commodity Option [Member] \| Cost of Sales [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Unrealized Gains (Losses) Recognized in Income	(653)	766	(115)	799
Commodity Futures [Member] \| Cost of Sales [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Unrealized Gains (Losses) Recognized in Income	653	3,357	(933)	1,751
Interest Rate Swap [Member] \| Interest Expense [Member] \| Derivatives in Cash Flow Hedging Relationships [Member] \| Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Recognized in OCI (Effective Portion)	(695)	(352)	(378)	226
Gains (Losses) Reclassified from Accumulated OCI into Income (Effective Portion)	(642)	(704)	(1,338)	(1,428)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	1,282		1,282		5,454
Fair value - liabilities	31		31		2,476
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	1,083		1,083		3,710
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	0		0		612
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	31		31		2,407
Not Designated as Hedging Instrument [Member] \| Commodity Option [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	0		0		69
Not Designated as Hedging Instrument [Member] \| Commodity Futures [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value - assets	199		199		1,132
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	3,637		3,637		4,596
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	2,638		2,638		2,662
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value - liabilities	$ 999		$ 999		$ 1,934