Fair Value Measurements - Assets and Liabilities Accounted for at Fair Value on a Recurring Basis (Details) - Recurring - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Assets:
Inventories carried at market	$ 4,805	$ 6,961
Cash equivalents	557	70
Marketable securities		246
Segregated investments and restricted cash equivalents	1,623	1,681
Total Assets	8,097	10,066
Liabilities:
Inventory-related payables	961	742
Total Liabilities	1,763	1,714
Commodity contracts
Assets:
Unrealized gains on derivative contracts	959	831
Liabilities:
Unrealized losses on derivative contracts	564	760
Foreign currency contracts
Assets:
Unrealized gains on derivative contracts	133	272
Liabilities:
Unrealized losses on derivative contracts	238	212
Interest rate contracts
Assets:
Unrealized gains on derivative contracts	20	5
Level 1
Assets:
Inventories carried at market	0	0
Cash equivalents	557	70
Marketable securities		246
Segregated investments and restricted cash equivalents	1,623	1,681
Total Assets	2,180	1,997
Liabilities:
Inventory-related payables	0	0
Total Liabilities	0	0
Level 1 | Commodity contracts
Assets:
Unrealized gains on derivative contracts	0	0
Liabilities:
Unrealized losses on derivative contracts	0	0
Level 1 | Foreign currency contracts
Assets:
Unrealized gains on derivative contracts	0	0
Liabilities:
Unrealized losses on derivative contracts	0	0
Level 1 | Interest rate contracts
Assets:
Unrealized gains on derivative contracts	0	0
Level 2
Assets:
Inventories carried at market	2,389	3,930
Cash equivalents	0	0
Marketable securities		0
Segregated investments and restricted cash equivalents	0	0
Total Assets	2,962	4,611
Liabilities:
Inventory-related payables	939	654
Total Liabilities	1,483	1,221
Level 2 | Commodity contracts
Assets:
Unrealized gains on derivative contracts	420	404
Liabilities:
Unrealized losses on derivative contracts	306	355
Level 2 | Foreign currency contracts
Assets:
Unrealized gains on derivative contracts	133	272
Liabilities:
Unrealized losses on derivative contracts	238	212
Level 2 | Interest rate contracts
Assets:
Unrealized gains on derivative contracts	20	5
Level 3
Assets:
Inventories carried at market	2,416	3,031
Cash equivalents	0	0
Marketable securities		0
Segregated investments and restricted cash equivalents	0	0
Total Assets	2,955	3,458
Liabilities:
Inventory-related payables	22	88
Total Liabilities	280	493
Level 3 | Commodity contracts
Assets:
Unrealized gains on derivative contracts	539	427
Liabilities:
Unrealized losses on derivative contracts	258	405
Level 3 | Foreign currency contracts
Assets:
Unrealized gains on derivative contracts	0	0
Liabilities:
Unrealized losses on derivative contracts	0	0
Level 3 | Interest rate contracts
Assets:
Unrealized gains on derivative contracts	$ 0	$ 0