Derivative Instruments - Cumulative Fair Value Hedging Adjustments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Cumulative basis adjustments for active hedging relationships	$ 1,172	$ (1,153)
Commodity contracts
Assets
Carrying amount of the hedged items	4,400	6,200
Long-term debt
Liabilities
Carrying amount of the hedged items	220,806	211,288
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Active hedging relationships	1,029	(3,711)
Discontinued hedging relationships	(9,007)	(9,332)
Total	(7,978)	(13,043)
Long-term debt | Not designated as hedges
Liabilities
Carrying amount of the hedged items	587	518
Beneficial interests issued by consolidated VIEs
Liabilities
Carrying amount of the hedged items	5,886	5,312
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Active hedging relationships	39	(30)
Discontinued hedging relationships	1	(5)
Total	40	(35)
Investment securities
Assets
Carrying amount of the hedged items	264,129	203,141
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Active hedging relationships	4,231	(1,675)
Discontinued hedging relationships	(1,549)	(1,959)
Total	2,682	(3,634)
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Amortized cost of the closed portfolio	97,600	72,800
Designated hedged items in active hedging relationships	72,000	41,200
Cumulative basis adjustments	391	(1,700)
Cumulative basis adjustments for active hedging relationships	1,200	(1,200)
Cumulative basis adjustments for discontinued hedging relationships	(781)	(566)
Investment securities | Not designated as hedges
Assets
Carrying amount of the hedged items	$ 34,700	$ 28,700