Derivative Instruments - Cumulative Fair Value Hedging Adjustments (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Cumulative basis adjustments for active hedging relationships	$ (1,228,000,000)	$ 73,000,000
Commodity contracts
Assets
Carrying amount of the hedged items	2,600,000,000	5,600,000,000
Long-term debt
Liabilities
Carrying amount of the hedged items	196,497,000,000	195,455,000,000
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Active hedging relationships	(4,124,000,000)	(2,042,000,000)
Discontinued hedging relationships	(9,427,000,000)	(9,727,000,000)
Total	(13,551,000,000)	(11,769,000,000)
Long-term debt | Not designated as hedges
Liabilities
Carrying amount of the hedged items	0	0
Beneficial interests issued by consolidated VIEs
Liabilities
Carrying amount of the hedged items	2,325,000,000	0
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Active hedging relationships	(23,000,000)	0
Discontinued hedging relationships	0	0
Total	(23,000,000)	0
Investment securities
Assets
Carrying amount of the hedged items	140,677,000,000	151,752,000,000
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Active hedging relationships	(1,704,000,000)	549,000,000
Discontinued hedging relationships	(1,992,000,000)	(2,010,000,000)
Total	(3,696,000,000)	(1,461,000,000)
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged items:
Amortized cost of the closed portfolio	69,300,000,000	83,900,000,000
Designated hedged items in active hedging relationships	59,000,000,000	68,000,000,000
Cumulative basis adjustments	(1,500,000,000)	(165,000,000)
Cumulative basis adjustments for active hedging relationships	(1,200,000,000)	73,000,000
Cumulative basis adjustments for discontinued hedging relationships	(304,000,000)	(238,000,000)
Investment securities | Not designated as hedges
Assets
Carrying amount of the hedged items	$ 15,900,000,000	$ 19,300,000,000