Supplemental Financial Information - Earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Sep. 29, 2019	Sep. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss)	$ 119	$ 46	$ (16)	$ 1,833	$ 66	$ 70	$ 149	$ 1,969
Less: Net income (loss) attributable to non-controlling interests	10			13			20	37
Net income (loss) attributable to stockholders	$ 109			$ 1,820			$ 129	$ 1,932
Weighted average number of shares outstanding (after deduction of treasury shares) during the year (in thousands) (in shares)	279,074			322,533			282,496	336,771
Options (in shares)	772			1,001			775	1,290
Restricted Share Units, Performance Share Units and Equity Rights (in shares)	3,672			1,733			2,548	1,730
Warrants (in shares)	0			0			0	0
Dilutive potential common share (in shares)	4,444			2,734			3,323	3,020
Adjusted weighted average number of share outstanding (after deduction of treasury shares) during the year (in thousands) (in shares)	283,518			325,267			285,819	339,791
Basic net income (loss) (in dollars per share)	$ 0.39			$ 5.64			$ 0.46	$ 5.74
Diluted net income (loss) (in dollars per share)	$ 0.38			$ 5.60			$ 0.45	$ 5.69
Maximum | Employee Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	100			300			100	100
Maximum | Restricted Stock Units Performance Share Units And Equity Rights
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	200			1,300			300	600
Maximum | Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	11,300			11,200			11,300	11,200
Common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Exercise price of warrants or rights (in dollars per share)	$ 131.39			$ 132.96			$ 131.39	$ 132.96