Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net loss on securities	$ (1)	$ (2)	$ 0
Income tax benefit	(29)	(176)	(210)
Net income (loss)	(79)	650	596
Interest expense	2,414	$ 696	$ 400
Reclassification from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net income (loss)	42
Reclassification from AOCI | Unrealized gains on available-for-sale securities:
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net loss on securities	0
Income tax benefit	0
Net income (loss)	0
Reclassification from AOCI | Unrealized gains on cash flow hedges:
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income tax benefit	(17)
Net income (loss)	48
Interest expense	65
Reclassification from AOCI | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of defined benefit pension plan items:	(7)
Income tax benefit	1
Net income (loss)	6
Reclassification from AOCI | Past service liability
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of defined benefit pension plan items:	0
Reclassification from AOCI | Actuarial losses
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of defined benefit pension plan items:	$ (7)