Income Taxes - Income Tax and Effective Rate (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 3,460	$ 1,318	$ 6,813	$ 2,239
Effective tax rate	15.70%	15.90%	15.70%	14.00%