Segment Reporting - Condensed Balance Sheets (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	$ 2,294			$ 2,951
Cash held at consolidated affiliated partnerships and restricted cash	2,440			2,995
Investments	2,585			3,012
Accounts receivable, net	476			485
Inventories, net	883			1,047
Related party notes receivable, net	7			11
Property, plant and equipment, net	3,865			3,969
Goodwill and intangible assets, net	712			754
Other assets	4,181			5,634
Total assets	17,443			20,858
Accounts payable, accrued expenses and other liabilities	3,490			4,105
Securities sold, not yet purchased, at fair value	2,679			3,473
Debt	6,447			7,207
Total liabilities	12,616			14,785
Equity attributable to Icahn Enterprises	2,645			3,208
Equity attributable to non-controlling interests	2,182			2,865
Total equity	4,827	$ 5,386	$ 5,625	6,073	$ 6,628	$ 7,187	$ 8,496	$ 9,558
Total Liabilities and Equity	17,443			20,858
Investment Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	5			23
Cash held at consolidated affiliated partnerships and restricted cash	2,254			2,799
Investments	2,476			2,898
Other assets	3,013			4,425
Total assets	7,748			10,145
Accounts payable, accrued expenses and other liabilities	802			1,312
Securities sold, not yet purchased, at fair value	2,679			3,473
Total liabilities	3,481			4,785
Equity attributable to Icahn Enterprises	2,745			3,243
Equity attributable to non-controlling interests	1,522			2,117
Total equity	4,267			5,360
Total Liabilities and Equity	7,748			10,145
Energy
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	534			1,179
Cash held at consolidated affiliated partnerships and restricted cash				7
Investments	95			100
Accounts receivable, net	281			286
Inventories, net	498			604
Property, plant and equipment, net	2,503			2,594
Goodwill and intangible assets, net	164			179
Other assets	307			310
Total assets	4,382			5,259
Accounts payable, accrued expenses and other liabilities	1,497			1,553
Debt	1,582			2,185
Total liabilities	3,079			3,738
Equity attributable to Icahn Enterprises	664			795
Equity attributable to non-controlling interests	639			726
Total equity	1,303			1,521
Total Liabilities and Equity	4,382			5,259
Automotive Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	111			104
Cash held at consolidated affiliated partnerships and restricted cash	6			9
Accounts receivable, net	34			41
Inventories, net	156			228
Property, plant and equipment, net	810			822
Goodwill and intangible assets, net	329			335
Other assets	484			480
Total assets	1,930			2,019
Accounts payable, accrued expenses and other liabilities	811			890
Debt	24			33
Total liabilities	835			923
Equity attributable to Icahn Enterprises	1,095			1,096
Total equity	1,095			1,096
Total Liabilities and Equity	1,930			2,019
Food Packaging Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	6			8
Accounts receivable, net	83			89
Inventories, net	111			111
Property, plant and equipment, net	126			134
Goodwill and intangible assets, net	22			23
Other assets	99			101
Total assets	447			466
Accounts payable, accrued expenses and other liabilities	117			148
Debt	142			133
Total liabilities	259			281
Equity attributable to Icahn Enterprises	172			168
Equity attributable to non-controlling interests	16			17
Total equity	188			185
Total Liabilities and Equity	447			466
Real Estate Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	27			22
Cash held at consolidated affiliated partnerships and restricted cash	2			4
Investments	14			14
Accounts receivable, net	18			16
Property, plant and equipment, net	370			363
Other assets	65			69
Total assets	496			488
Accounts payable, accrued expenses and other liabilities	47			43
Debt	2			1
Total liabilities	49			44
Equity attributable to Icahn Enterprises	442			439
Equity attributable to non-controlling interests	5			5
Total equity	447			444
Total Liabilities and Equity	496			488
Home Fashion Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	5			5
Cash held at consolidated affiliated partnerships and restricted cash	3			3
Accounts receivable, net	28			26
Inventories, net	96			81
Property, plant and equipment, net	52			52
Goodwill and intangible assets, net	20			19
Other assets	17			17
Total assets	221			203
Accounts payable, accrued expenses and other liabilities	43			42
Debt	14			8
Total liabilities	57			50
Equity attributable to Icahn Enterprises	164			153
Total equity	164			153
Total Liabilities and Equity	221			203
Pharma
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	40			26
Accounts receivable, net	32			27
Inventories, net	22			23
Goodwill and intangible assets, net	177			198
Other assets	7			8
Total assets	278			282
Accounts payable, accrued expenses and other liabilities	57			55
Total liabilities	57			55
Equity attributable to Icahn Enterprises	221			227
Total equity	221			227
Total Liabilities and Equity	278			282
Holding Company
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	1,566			1,584
Cash held at consolidated affiliated partnerships and restricted cash	175			173
Related party notes receivable, net	7			11
Property, plant and equipment, net	4			4
Other assets	189			224
Total assets	1,941			1,996
Accounts payable, accrued expenses and other liabilities	116			62
Debt	4,683			4,847
Total liabilities	4,799			4,909
Equity attributable to Icahn Enterprises	(2,858)			(2,913)
Total equity	(2,858)			(2,913)
Total Liabilities and Equity	$ 1,941			$ 1,996