Equity (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period (in shares)			134,000,000
Balance at beginning of period	$ 31,978	$ 32,586	$ 31,672	$ 33,070
Net income (loss)	604	272	1,276	580
Distributions paid to noncontrolling interests	(1)	(1)	(1)	(1)
Other comprehensive loss	(389)	215	(301)	57
Share-based compensation	94	61	155	127
Shares issued under stock plans	10	(13)	(5)	(101)
Purchases of treasury stock	(500)	(588)	(1,000)	(1,200)
Retirement of treasury stock (see Note 18)		0		0
Capital contribution from noncontrolling interest	$ 13		$ 13
Balance at end of period (in shares)	141,000,000		141,000,000
Balance at end of period	$ 31,809	32,532	$ 31,809	32,532
Net income attributable to redeemable noncontrolling interest	5	12	15	22
Distributions paid to redeemable noncontrolling interests	$ 8	$ 10	$ 21	$ 20
Common Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period (in shares)	784,000,000	789,000,000	784,000,000	789,000,000
Balance at beginning of period	$ 8	$ 8	$ 8	$ 8
Retirement of treasury stock (in shares)		(5,000,000)		(5,000,000)
Balance at end of period (in shares)	784,000,000	784,000,000	784,000,000	784,000,000
Balance at end of period	$ 8	$ 8	$ 8	$ 8
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period (in shares)	137,000,000	123,000,000	134,000,000	121,000,000
Balance at beginning of period	$ (6,561)	$ (4,888)	$ (6,140)	$ (4,375)
Shares issued under stock plans (in shares)	(1,000,000)	0	(3,000,000)	(3,000,000)
Shares issued under stock plans	$ 44	$ 22	$ 123	$ 121
Purchases of treasury stock (in shares)	5,000,000	5,000,000	10,000,000	10,000,000
Purchases of treasury stock	$ (500)	$ (588)	$ (1,000)	$ (1,200)
Retirement of treasury stock (in shares)		(5,000,000)		(5,000,000)
Retirement of treasury stock (see Note 18)		$ 588		$ 588
Balance at end of period (in shares)	141,000,000	123,000,000	141,000,000	123,000,000
Balance at end of period	$ (7,017)	$ (4,866)	$ (7,017)	$ (4,866)
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	22,950	23,522	22,983	23,643
Share-based compensation	94	61	155	127
Shares issued under stock plans	(34)	(35)	(128)	(222)
Retirement of treasury stock (see Note 18)		(588)		(588)
Balance at end of period	23,010	22,960	23,010	22,960
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	(640)	(536)	(745)	(387)
Other comprehensive loss	(365)	213	(260)	64
Balance at end of period	(1,005)	(323)	(1,005)	(323)
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	15,515	13,745	14,846	13,441
Net income (loss)	598	269	1,267	573
Balance at end of period	16,113	14,014	16,113	14,014
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	706	735	720	740
Net income (loss)	6	3	9	7
Distributions paid to noncontrolling interests	(1)	(1)	(1)	(1)
Other comprehensive loss	(24)	2	(41)	(7)
Capital contribution from noncontrolling interest	13		13
Balance at end of period	$ 700	$ 739	$ 700	$ 739