Pension and Postretirement Benefits (Details 4)	12 Months Ended
	May 27, 2012	May 29, 2011	May 30, 2010
Pension Benefits [Member]
Weighted Average Actuarial Assumption Used to Determine Net Expense
Discount rate	5.30%	5.80%	6.90%
Long-term rate of return on plan assets	7.75%	7.75%	7.75%
Long-term rate of compensation increase	4.25%	4.25%	4.25%
Other Benefits [Member]
Weighted Average Actuarial Assumption Used to Determine Net Expense
Discount rate	4.30%	5.40%	6.60%
Long-term rate of return on plan assets		3.50%	4.50%