Income Taxes - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Jan. 01, 2018	Dec. 22, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Earnings before income taxes			$ 4,316	$ 4,304	$ 3,142
Income tax adjustment benefit			77	62	21
Non-cash credit to income tax expense		$ 3,500	0	0	3,506
Non-cash credit to income tax expense amount per share (in dollars per share)		$ 3.81
U.S. corporate tax rate	21.00%
Unrecognized tax benefits			13	12	24
Amount of unrecognized tax benefits that may favorably effect the effective income tax rate			10	9	19
Expense (benefit) for changes to reserves for interest and penalties for prior year tax positions			1	(3)	3
Previously recorded liabilities for interest and penalties of prior period tax positions			$ 2	$ 2	$ 6