Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ (2,320)	$ 1,645	$ (1,756)	$ 2,960
Decrease in income before income tax expense	16,540		16,340
Income (loss) before income tax expense	$ (10,597)	$ 5,935	$ (6,452)	$ 9,892
Effective tax rates	22.00%	28.00%	27.00%	30.00%