Pensions and Other Post-Retirement Benefits 5 (Details) (USD $) In Thousands	12 Months Ended
Apr. 27, 2011	Apr. 28, 2010
Pension Benefits [Member]
Accumulated other comprehensive loss, before tax
Net actuarial loss	$ 909,796	$ 1,085,471
Prior service cost/(credit)	28,649	30,683
Net amount recognized	938,445	1,116,154
Accumulated other comprehensive loss (income) expected to be recognized as components of net periodic benefit costs/(credits)
Net actuarial loss	85,932	76,963
Prior service cost/(credit)	2,020	2,373
Net amount recognized	87,952	79,336
Other Retiree Benefits [Member]
Accumulated other comprehensive loss, before tax
Net actuarial loss	11,816	17,206
Prior service cost/(credit)	(20,335)	(21,780)
Net amount recognized	(8,519)	(4,574)
Accumulated other comprehensive loss (income) expected to be recognized as components of net periodic benefit costs/(credits)
Net actuarial loss	1,095	1,604
Prior service cost/(credit)	(6,116)	(5,155)
Net amount recognized	$ (5,021)	$ (3,551)

The pretax total of net (gain) loss, prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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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The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

+ References

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Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The amounts in accumulated other comprehensive income related to gains and losses that are not recognized immediately and are expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

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-Number 132R
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The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

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-Number 132R
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The aggregate amount in accumulated other comprehensive income expected to be recognized as a component of net periodic benefit cost over the fiscal year that follows the most recent annual statement of financial position presented (including the net gain or loss, net prior service cost or credit, and net transition asset or obligation).

+ References

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