Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 1,362	$ 1,709	$ 3,594	$ 5,139
Net actuarial losses of defined benefit plans:
Adjustments, net of tax effect of $5 and ($3); $2 and ($4)	(11)	6	(5)	6
Recognized within net income, net of tax effect of ($1) and ($1); ($3) and ($3)	2	3	7	9
Prior service cost (credit) of defined benefit plans:
Recognized within net income, net of tax effect of $0 and $0; $0 and $0	1	1	1	1
Derivative instruments:
Change in fair value, net of tax effect of $0 and $0; $0 and $0	0	0	1	1
Available-for-sale investments:
Unrealized gains (losses), net of tax effect of ($4) and $0; ($2) and $0	13	1	6	2
Other comprehensive income (loss), net of taxes	5	11	10	19
Total comprehensive income	$ 1,367	$ 1,720	$ 3,604	$ 5,158