Pension and Postretirement Benefits (Details 7)	12 Months Ended
	May 27, 2012	May 29, 2011
Weighted average asset allocation and target asset allocation
Total	100.00%	100.00%
Target Allocations	100.00%
Equity securities [Member]
Weighted average asset allocation and target asset allocation
Total	41.00%	49.00%
Target Allocations	38.00%
Debt securities [Member]
Weighted average asset allocation and target asset allocation
Total	23.00%	22.00%
Target Allocations	22.00%
Real estate funds [Member]
Weighted average asset allocation and target asset allocation
Total	3.00%	3.00%
Target Allocations	6.00%
Multi-strategy hedge funds [Member]
Weighted average asset allocation and target asset allocation
Total	14.00%	14.00%
Target Allocations	15.00%
Private equity [Member]
Weighted average asset allocation and target asset allocation
Total	2.00%	2.00%
Target Allocations	7.00%
Other [Member]
Weighted average asset allocation and target asset allocation
Total	17.00%	10.00%
Target Allocations	12.00%