Equity (Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 53,564	$ 44,554	$ 48,326	$ 45,424
Net other comprehensive income (loss)	(32)	(78)	(11)	(140)
Ending balance	56,250	46,746	56,250	46,746
Net Unrealized Gains (Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	21	19	20	14
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	0	1	5
Net other comprehensive income (loss)	0	0	1	5
Less other comprehensive (income) loss attributable to noncontrolling interests	0	0	0	0
Ending balance	21	19	21	19
Net Unrealized Gains (Losses) on Available for Sale Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(63)	(53)	(69)	5
Other comprehensive income (loss) before reclassifications	(19)	(31)	(20)	(91)
Amounts reclassified from AOCI	2	1	9	3
Net other comprehensive income (loss)	(17)	(30)	(11)	(88)
Less other comprehensive (income) loss attributable to noncontrolling interests	0	0	0	0
Ending balance	(80)	(83)	(80)	(83)
Defined Benefit Pension and Other Benefits Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(100)	25	(101)	25
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	0	1	0
Net other comprehensive income (loss)	0	0	1	0
Less other comprehensive (income) loss attributable to noncontrolling interests	0	0	0	0
Ending balance	(100)	25	(100)	25
Net Unrealized Gains (Losses) on Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(64)	(55)	(74)	(49)
Other comprehensive income (loss) before reclassifications	(15)	(49)	(2)	(58)
Amounts reclassified from AOCI	0	0	0	0
Net other comprehensive income (loss)	(15)	(49)	(2)	(58)
Less other comprehensive (income) loss attributable to noncontrolling interests	5	23	2	26
Ending balance	(74)	(81)	(74)	(81)
Other Comprehensive Income Related to Equity Method Investees
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	6	5	6	5
Other comprehensive income (loss) before reclassifications	0	1	0	1
Amounts reclassified from AOCI	0	0	0	0
Net other comprehensive income (loss)	0	1	0	1
Less other comprehensive (income) loss attributable to noncontrolling interests	0	0	0	0
Ending balance	6	6	6	6
Total
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(200)	(59)	(218)	0
Other comprehensive income (loss) before reclassifications	(34)	(79)	(22)	(148)
Amounts reclassified from AOCI	2	1	11	8
Net other comprehensive income (loss)	(32)	(78)	(11)	(140)
Less other comprehensive (income) loss attributable to noncontrolling interests	5	23	2	26
Ending balance	(227)	(114)	(227)	(114)
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	(15)	(21)	(15)	(21)
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	$ (15)	$ (21)	$ (15)	$ (21)