Supplemental Financial Information - Earnings per share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 28, 2020	Mar. 29, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 28, 2020	Jun. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss)	$ (209)	$ (13)	$ 46	$ (16)	$ (222)	$ 30
Less: Net income (loss) attributable to non-controlling interests	5		5		13	10
Net income (loss) attributable to stockholders	$ (214)		$ 41		$ (235)	$ 20
Weighted average number of shares outstanding (after deduction of treasury shares) during the year (in thousands) (in shares)	279,142,000		281,241,000		279,533,000	284,217,000
Options (in shares)	0		767,000		0	771,000
Restricted Share Units, Performance Share Units and Equity Rights (in shares)	0		3,080,000		0	1,870,000
Warrants (in shares)	0		0		0	0
Dilutive potential common shares (in shares)	0		3,847,000		0	2,641,000
Adjusted weighted average number of shares outstanding (after deduction of treasury shares) during the year (in thousands) (in shares)	279,142,000		285,088,000		279,533,000	286,858,000
Basic net income (loss) (in dollars per share)	$ (0.77)		$ 0.15		$ (0.84)	$ 0.07
Diluted net income (loss) (in dollars per share)	$ (0.77)		$ 0.14		$ (0.84)	$ 0.07
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)	900,000		100,000		900,000	100,000
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)	7,700,000		300,000		7,700,000	300,000
Maximum | Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0		11,300,000
Common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Exercise price of warrants or rights (in dollars per share)			$ 131.84			$ 131.84