Other Comprehensive Income (Loss), Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Dec. 30, 2017	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (683)		$ 862
Other comprehensive income (loss) before reclassifications	314
Amounts reclassified out of accumulated other comprehensive income	(9)	$ (240)
Tax effects	(60)
Other comprehensive income (loss)	245	757
Unrealized holding gains (losses) on available-for-sale investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	0		1,745	$ 0
Other comprehensive income (loss) before reclassifications	0
Amounts reclassified out of accumulated other comprehensive income	0
Tax effects	0
Other comprehensive income (loss)	0
Unrealized holding gains (losses) on derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	249		106	130
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification			24
Other comprehensive income (loss) before reclassifications	203
Amounts reclassified out of accumulated other comprehensive income	(53)
Tax effects	(31)
Other comprehensive income (loss)	119
Actuarial gains (losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	(880)		(963)	(1,028)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification			(65)
Other comprehensive income (loss) before reclassifications	140
Amounts reclassified out of accumulated other comprehensive income	45	$ 24
Tax effects	(37)
Other comprehensive income (loss)	148
Foreign currency translation adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	(52)		(26)	(30)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification			(4)
Other comprehensive income (loss) before reclassifications	(29)
Amounts reclassified out of accumulated other comprehensive income	(1)
Tax effects	8
Other comprehensive income (loss)	(22)
Accumulated other comprehensive income (loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	$ (683)		862	$ (928)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification			(1,790)
Accounting Standards Update 2016-01 [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax			$ (1,745)