Income Taxes Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Examination, Penalties and Interest Expense [Abstract]
Change in enacted tax rate, amount			$ (7,300)
U.S. Federal statutory income tax rate	21.00%	21.00%	35.00%
Effective tax rate	24.40%	24.00%	(78.60%)
Effective tax rate, before impact arising from Tax Act			37.40%
Unrecognized tax benefits	$ 46	$ 50	$ 57	$ 62
Unrecognized tax benefits that would impact effective tax rate	33
Liability recorded for interest on income taxes expense	$ 7