Shareholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Mar. 01, 2017
Equity [Abstract]
Stock repurchase program, number of shares authorized to be repurchased					10.0
Remaining number of shares authorized to be repurchased (shares)	5.1		5.1
Stock repurchased during the period (shares)			2.5	5.9
Stock repurchased during the period, value			$ 522	$ 1,100
Shares remaining to be repurchased as a percent of total shares outstanding	2.00%		2.00%
Dividends declared per share	$ 0.93	$ 0.84	$ 2.79	$ 2.52
Dividends paid in cash	$ 275	$ 252	$ 801	$ 735
Recognized net actuarial losses (before tax)			280	255
Amortization of prior service credit (before tax)			$ 36	$ 53