Summary of Major Components of Merger, Restructuring and Other Operating Expenses, Net (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Merger related expenses
Merger related expenses, Severance, retention, and relocation									$ 148	$ 92
Merger related expenses, Transaction and integration									124	80
Merger related expenses, Other related expenses									60	8
Total Merger related expenses									332	180
Restructuring and certain other expenses									71	21	56
Total Merger, restructuring and other operating expenses, net	$ 128	$ 72	$ 103	$ 101	$ 111	$ 44	$ 26	$ 19	$ 403	$ 201	$ 56