Income Taxes (Components of Income Tax Provision) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Income Tax Disclosure [Abstract]
Income tax provision	$ 93	$ 65	$ 237	$ 196
Percentage change in income tax provision	0.431	0.209	0.431	0.209
Effective tax rate	26.10%	30.20%	25.10%	25.60%