Cash and Investments, Available For Sale Investments (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Available-for-sale Securities [Abstract]
Fair Value	$ 16,047
Adjusted Cost, Total	19,311	$ 9,253
Gross Unrealized Gains, Total	2,710	3,794
Gross Unrealized Losses, Total	(14)	(9)
Fair Value, Total	22,007	13,038
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds	2,200	1,700	$ 1,300
Available-for-sale Securities, Gross Realized Gains	133	136	146
Due in 1 year or less, Fair Value	5,893
Due in 1-2 years, Fair Value	1,268
Due in 2-5 years, Fair Value	620
Instruments not due at a single maturity date, Fair Value	8,266
Cash and Cash Equivalents [Member]
Available-for-sale Securities [Abstract]
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds	144	509	$ 339
Asset-backed securities
Available-for-sale Securities [Abstract]
Adjusted Cost	5	8
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	(2)
Fair Value	4	6
Corporate debt
Available-for-sale Securities [Abstract]
Adjusted Cost	4,164	2,040
Gross Unrealized Gains	3	13
Gross Unrealized Losses	(10)	(5)
Fair Value	4,157	2,048
Financial institution instruments
Available-for-sale Securities [Abstract]
Adjusted Cost	11,140	3,146
Gross Unrealized Gains	1	2
Gross Unrealized Losses	(2)	(1)
Fair Value	11,139	3,147
Government debt
Available-for-sale Securities [Abstract]
Adjusted Cost	748	741
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	(1)
Fair Value	747	740
Marketable equity securities
Available-for-sale Securities [Abstract]
Adjusted Cost	3,254	3,318
Gross Unrealized Gains	2,706	3,779
Gross Unrealized Losses	0	0
Fair Value	5,960	$ 7,097
Debt Securities [Member]
Available-for-sale Securities [Abstract]
Adjusted Cost	16,057
Due in 1 year or less, Cost	5,896
Due in 1-2 years, Cost	1,271
Due in 2-5 years, Cost	623
Instruments not due at a single maturity date, Cost	$ 8,267