Benefit Plans (Tables)

9 Months Ended

Oct. 27, 2012

Pension and Other Postretirement Benefit Expense [Abstract]

Schedule of Net Periodic Benefit Costs

The actuarially determined components of the net periodic benefit cost are as follows:

	13 Weeks Ended						39 Weeks Ended
	October 27, 2012			October 29, 2011			October 27, 2012			October 29, 2011
	(millions)
Pension Plan
Service cost	$	30		$	25		$	88		$	76
Interest cost	40			40			118			120
Expected return on assets	(64		)	(61		)	(190		)	(185		)
Recognition of net actuarial loss	35			22			106			66
Amortization of prior service credit	(1		)	(1		)	(1		)	(1		)
	$	40		$	25		$	121		$	76
Supplementary Retirement Plan
Service cost	$	1		$	1		$	4		$	4
Interest cost	9			9			26			27
Recognition of net actuarial loss	4			2			13			6
Amortization of prior service credit	—			—			—			(1		)
	$	14		$	12		$	43		$	36
Postretirement Obligations
Service cost	$	—		$	—		$	—		$	—
Interest cost	3			3			9			10
Recognition of net actuarial gain	(1		)	(1		)	(3		)	(4		)
Amortization of prior service cost	—			—			—			—
	$	2		$	2		$	6		$	6