Additional Financial Information - Balance Sheet Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Prepaid expenses and other
Prepaid taxes	$ 1,093	$ 1,200
Deferred contract costs	2,432	2,472
Restricted cash	1,094	1,195
Other prepaid expense and other	2,287	1,843
Prepaid expenses and other	6,906	6,710
Accounts payable and accrued liabilities
Accounts payable	8,040	6,667
Accrued expenses	9,123	6,050
Accrued vacation, salaries and wages	4,485	5,057
Interest payable	1,561	1,452
Taxes payable	1,624	1,432
Total accounts payable and accrued liabilities	24,833	20,658
Other current liabilities
Dividends payable	2,709	2,618
Contract liability	6,053	4,843
Other	2,263	2,167
Total other current liabilities	11,025	9,628
Expenditures incurred but not yet paid	$ 5,900	$ 4,100