Goodwill and Intangible Assets - Change in Company's Goodwill and Intangible Assets (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 07, 2013	Feb. 23, 2013
Goodwill [Line Items]
Finite-Lived intangible Assets, Accumulated Amortization	$ 75	$ 67
Customer Lists, Pharmacy Scripts, Favorable Operating Leases and Other [Member]
Goodwill [Line Items]
Finite-Lived intangible Assets, Accumulated Amortization	73	65
Non-Compete Agreements [Member]
Goodwill [Line Items]
Finite-Lived intangible Assets, Accumulated Amortization	$ 2	$ 2