Other Financial Data - Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016	Aug. 25, 2015
Basic earnings (loss) per common share:
Earnings	$ 212,000,000	$ 192,000,000	$ 420,000,000	$ 317,000,000
Weighted average common shares outstanding (in shares)	162.3	166.3	163.2	171.0
Basic earnings per share amount (in US$ per share)	$ 1.30	$ 1.15	$ 2.57	$ 1.85
Diluted earnings per common share:
Earnings	$ 212,000,000	$ 192,000,000	$ 420,000,000	$ 317,000,000
Weighted average common shares outstanding (in shares)	162.3	166.3	163.2	171.0
Add effect of dilutive securities:
Share-based awards (in shares)	3.4	2.4	3.3	2.5
Senior Convertible Notes (in shares)	3.3	0.9	2.8	0.5
Diluted weighted average common shares outstanding (in shares)	169.0	169.6	169.3	174.0
Per share amount (in US$ per share)	$ 1.25	$ 1.13	$ 2.48	$ 1.82
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive impact of Senior Convertible Notes (in shares)	3.3	0.9	2.8	0.5
Senior Convertible Notes \| Convertible Notes
Add effect of dilutive securities:
Senior Convertible Notes (in shares)	3.3	0.9	2.8	0.5
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Debt instrument face amount					$ 1,000,000,000
Interest rate					2.00%
Dilutive impact of Senior Convertible Notes (in shares)	3.3	0.9	2.8	0.5
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of dilutive shares due to antidilutive nature (in shares)	2.0	2.5	2.3	2.9
Performance Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of dilutive shares due to antidilutive nature (in shares)	1.7	1.8	1.9	2.0
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of dilutive shares due to antidilutive nature (in shares)				0.4

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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