Equity (Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 44,049	$ 45,730	$ 45,424	$ 44,929
Total other comprehensive income (loss), net of tax	(48)	16	(62)	12
Ending balance	44,554	45,114	44,554	45,114
Net Unrealized Gains (Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	18	10	14	8
Other comprehensive loss before reclassifications	0	0	0	0
Amounts reclassified from AOCI	1	2	5	4
Total other comprehensive income (loss), net of tax	1	2	5	4
Less other comprehensive loss attributable to noncontrolling interests	0	0	0	0
Ending balance	19	12	19	12
Net Unrealized Gains (Losses) on Available for Sale Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(25)	9	5	20
Other comprehensive loss before reclassifications	(30)	1	(60)	(7)
Amounts reclassified from AOCI	2	1	2	(2)
Total other comprehensive income (loss), net of tax	(28)	2	(58)	(9)
Less other comprehensive loss attributable to noncontrolling interests	0	0	0	0
Ending balance	(53)	11	(53)	11
Defined Benefit Pension and Other Benefits Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	25	(74)	25	(75)
Other comprehensive loss before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	1	0	2
Total other comprehensive income (loss), net of tax	0	1	0	2
Less other comprehensive loss attributable to noncontrolling interests	0	0	0	0
Ending balance	25	(73)	25	(73)
Net Unrealized Gains (Losses) on Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(43)	(47)	(49)	(49)
Other comprehensive loss before reclassifications	(21)	11	(9)	15
Amounts reclassified from AOCI	0	0	0	0
Total other comprehensive income (loss), net of tax	(21)	11	(9)	15
Less other comprehensive loss attributable to noncontrolling interests	9	(3)	3	(5)
Ending balance	(55)	(39)	(55)	(39)
Other Comprehensive Income (Loss) Related to Equity Method Investees
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	5	4	5	4
Other comprehensive loss before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	0	0	0
Total other comprehensive income (loss), net of tax	0	0	0	0
Less other comprehensive loss attributable to noncontrolling interests	0	0	0	0
Ending balance	5	4	5	4
Total
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(20)	(98)	0	(92)
Other comprehensive loss before reclassifications	(51)	12	(69)	8
Amounts reclassified from AOCI	3	4	7	4
Total other comprehensive income (loss), net of tax	(48)	16	(62)	12
Less other comprehensive loss attributable to noncontrolling interests	9	(3)	3	(5)
Ending balance	(59)	(85)	(59)	(85)
Net Unrealized Gains (Losses) on Cash Flow Hedges. Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance	0	0	0	0
Net Unrealized Gains (Losses) on Available for Sale Securities, Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance	0	0	0	0
Defined Benefit Pension and Other Benefits Plans, Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance	0	0	0	0
Net Unrealized Gains (Losses) on Foreign Currency Translation, Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance	2	(13)	2	(13)
Other Comprehensive Income (Loss) Related to Equity Method Investees, Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance	0	0	0	0
Total, Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance	$ 2	$ (13)	$ 2	$ (13)