Benefit Plans - Net Periodic Benefit Expense and Contributions for Defined Benefit Pension Plans and Other Postretirement Benefit Plans (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 06, 2014	Sep. 07, 2013	Sep. 06, 2014	Sep. 07, 2013
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost
Interest cost	27	28	66	65
Expected return on assets	(36)	(33)	(83)	(76)
Amortization of prior service benefit
Amortization of net actuarial loss	15	24	34	55
Net periodic benefit expense	6	19	17	44
Contributions to benefit plans	(22)	(21)	(67)	(92)
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost				1
Interest cost	1	1	2	2
Expected return on assets
Amortization of prior service benefit	(4)	(3)	(8)	(7)
Amortization of net actuarial loss	1	1	2	3
Net periodic benefit expense	(2)	(1)	(4)	(1)
Contributions to benefit plans	$ (1)	$ (2)	$ (1)	$ (3)