Other Financial Data (Changes in Accumulated Other Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 04, 2015	Mar. 29, 2014	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	$ 2,766
Other comprehensive income (loss), net of tax	(58)	17
Balance at end of period	2,094
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(1,855)
Other comprehensive income (loss), net of tax	(58)
Balance at end of period	(1,913)	(2,270)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(204)	(96)
Other comprehensive income (loss) before reclassification adjustment	(27)	3
Other comprehensive income (loss), tax	1	(1)
Other comprehensive income (loss), net of tax	(26)	2
Balance at end of period	(230)	(94)
Net loss on derivative instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period			0	(1)
Balance at end of period	0	(1)	0	(1)
Unrealized Gains and Losses on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	44	(2)
Other comprehensive income (loss) before reclassification adjustment	(7)	0
Other comprehensive income (loss) before reclassification adjustment, tax	3	2
Other comprehensive income (loss) before reclassification adjustment, net of tax	(4)	2
Reclassification adjustment	(46)	0
Tax expense (benefit)	17	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(29)	0
Other comprehensive income (loss), net of tax	(33)	2
Balance at end of period	11	0
Defined Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(1,695)	(2,188)
Tax expense (benefit)	(1)	(6)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1	13
Balance at end of period	(1,694)	(2,175)
Defined Benefit Plans - Actuarial net losses
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Reclassification adjustment	19	29
Defined Benefit Plans - Prior service benefits
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Reclassification adjustment	$ (17)	$ (10)