Fair Value Measurements and Financial Instruments - Fair Value of Short-term and Long-term Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument fair value	$ 84,385	$ 106,599
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument fair value	54,656	62,606
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument fair value	0	0
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument fair value	148,906	149,543
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument fair value	$ 139,041	$ 169,205