Key Assumptions (Detail)	12 Months Ended
Oct. 01, 2011	Oct. 02, 2010	Oct. 03, 2009
Assumptions:
Discount rate			7.80%
Rate of return on plan assets			7.50%
Salary increases			5.00%
Pension Plans
Assumptions:
Discount rate	4.75%	5.25%	5.75%
Rate of return on plan assets	7.75%	7.75%	7.75%
Salary increases	4.00%	4.00%	4.50%
Postretirement Medical Plans
Assumptions:
Discount rate	4.75%	5.25%	5.75%
Rate of return on plan assets	7.75%	7.75%	7.75%
Year 1 increase in cost of benefits	8.00%	8.25%	8.50%
Rate of increase to which the cost of benefits is assumed to decline (the ultimate trend rate)	4.50%	4.75%	5.00%
Year that the rate reaches the ultimate trend rate	2025	2022	2019

The interest rate used to adjust for the time value of money.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

-Topic 715

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- Definition

Expected rate of compensation increases (for pay-related plans).

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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

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-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

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The ultimate trend rate for health care costs.

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The year when the ultimate health care cost trend rate is expected to be reached.

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