Assets and Liabilities Measured at Fair Value - Realized and Unrealized Gains (Losses) on Financial Instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Assets and Liabilities Measured at Fair Value
Realized and unrealized gains (losses) on financial instruments, net	$ 106	$ (40)	$ 545	$ 66
Debt and equity securities
Assets and Liabilities Measured at Fair Value
Realized and unrealized gains (losses) on financial instruments, net	2	(6)	(10)	210
Debt measured at fair value
Assets and Liabilities Measured at Fair Value
Realized and unrealized gains (losses) on financial instruments, net	45	(57)	691	(241)
Gain (loss) on changes in fair value	(41)	(46)	0	(114)
Cumulative amount of gain in changes in fair value	68		68
Change in fair value of bond hedges
Assets and Liabilities Measured at Fair Value
Realized and unrealized gains (losses) on financial instruments, net	21	18	(248)	77
Other
Assets and Liabilities Measured at Fair Value
Realized and unrealized gains (losses) on financial instruments, net	$ 38	$ 5	$ 112	$ 20