Annual report pursuant to Section 13 and 15(d)

Postretirement Health Care and Life Insurance Benefits (Assumed Health Care Cost Trend Rates) (Details)

v2.4.0.6
Postretirement Health Care and Life Insurance Benefits (Assumed Health Care Cost Trend Rates) (Details)
12 Months Ended
Jan. 28, 2012
Jan. 29, 2011
Rates to which is the cost trend rate is assumed to decline (the ultimate trend rate) 5.00% 5.00%
Year that the rate reaches the ultimate trend rate 2022 2022
Minimum [Member]
   
Health care cost trend rates assumed for the next year 8.08% 8.38%
Maximum [Member]
   
Health care cost trend rates assumed for the next year 9.62% 10.08%