Taxes - Schedule of Cash Taxes Paid (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income taxes, net of amounts refunded	$ 3,040	$ 2,725	$ 3,583
Employment taxes	1,225	618	1,044
Property and other taxes	1,756	2,093	1,551
Total	$ 6,021	$ 5,436	$ 6,178