Earnings Per Share - Narrative (Details) - USD ($) shares in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2017	Dec. 31, 2017	Dec. 30, 2016	Dec. 25, 2015	Oct. 25, 2017	Apr. 30, 2017	Apr. 30, 2015
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)		7.6	2.8	2.5
Share Repurchase Program April 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program							$ 2,000,000,000
Share Repurchase Program April 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program						$ 1,000,000,000
Share repurchase program, additional authorized amount	$ 500,000,000
Share Repurchase Program October 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program					$ 1,500,000,000.0