Segment Reporting - Condensed Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	$ 2,221	$ 2,991	$ 6,827	$ 8,433
Other revenues from operations	192	203	566	588
Net loss from investment activities	257	(332)	(318)	(1,275)
Interest and dividend income	115	143	380	481
(Loss) gain on disposition of assets, net	(1)	2	(6)	5
Other income (loss), net	7	3	13	6
Total revenues	2,791	3,010	7,462	8,238
Cost of goods sold	2,223	2,377	6,414	6,947
Other expenses from operations	155	165	462	483
Dividend expense	14	21	47	68
Selling, general and administrative	202	209	578	653
Restructuring, net		1	1	1
Credit loss on related party note receivable		23		139
Loss on deconsolidation of subsidiary				246
Interest expense	130	148	394	426
Total Expenses	2,724	2,944	7,896	8,963
Pre-tax loss	67	66	(434)	(725)
Income tax (expense) benefit	13	(96)	2	(82)
Net (loss) income	80	(30)	(432)	(807)
Less: net income (loss) attributable to non-controlling interests	58	(24)	(85)	(262)
Net income (loss) attributable to Icahn Enterprises	22	(6)	(347)	(545)
Capital expenditures	58	70	192	201
Depreciation and amortization	126	133	382	384
Investment Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net loss from investment activities	257	(332)	(318)	(1,275)
Interest and dividend income	77	108	269	386
Other income (loss), net				1
Total revenues	334	(224)	(49)	(888)
Dividend expense	14	21	47	68
Selling, general and administrative	5	3	15	19
Interest expense	19	49	63	132
Total Expenses	38	73	125	219
Pre-tax loss	296	(297)	(174)	(1,107)
Net (loss) income	296	(297)	(174)	(1,107)
Less: net income (loss) attributable to non-controlling interests	104	(131)	(86)	(555)
Net income (loss) attributable to Icahn Enterprises	192	(166)	(88)	(552)
Energy
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	1,834	2,522	5,663	7,045
Interest and dividend income	10	10	30	23
(Loss) gain on disposition of assets, net		(1)	(1)	(1)
Other income (loss), net	2	4	10	10
Total revenues	1,846	2,535	5,702	7,077
Cost of goods sold	1,914	2,048	5,549	5,964
Selling, general and administrative	47	43	124	128
Interest expense	27	22	86	67
Total Expenses	1,988	2,113	5,759	6,159
Pre-tax loss	(142)	422	(57)	918
Income tax (expense) benefit	8	(80)	26	(173)
Net (loss) income	(134)	342	(31)	745
Less: net income (loss) attributable to non-controlling interests	(46)	107		292
Net income (loss) attributable to Icahn Enterprises	(88)	235	(31)	453
Capital expenditures	34	50	124	150
Depreciation and amortization	90	96	272	269
Automotive Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	206	264	637	799
Other revenues from operations	168	180	504	527
Interest and dividend income	1	1	3	1
(Loss) gain on disposition of assets, net	(1)	3	(5)	6
Total revenues	374	448	1,139	1,333
Cost of goods sold	167	174	461	540
Other expenses from operations	137	148	412	435
Selling, general and administrative	102	116	303	362
Interest expense	1	2	2	3
Total Expenses	407	440	1,178	1,340
Pre-tax loss	(33)	8	(39)	(7)
Income tax (expense) benefit	9	(1)	13	5
Net (loss) income	(24)	7	(26)	(2)
Net income (loss) attributable to Icahn Enterprises	(24)	7	(26)	(2)
Capital expenditures	12	17	40	38
Depreciation and amortization	19	17	56	58
Food Packaging Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	101	105	307	340
Other income (loss), net	(1)	(2)	(3)	(8)
Total revenues	100	103	304	332
Cost of goods sold	86	83	252	264
Selling, general and administrative	12	14	36	43
Restructuring, net			1
Interest expense	2	3	8	9
Total Expenses	100	100	297	316
Pre-tax loss		3	7	16
Income tax (expense) benefit		(3)	(3)	(4)
Net (loss) income			4	12
Less: net income (loss) attributable to non-controlling interests			1	1
Net income (loss) attributable to Icahn Enterprises			3	11
Capital expenditures	5	2	10	9
Depreciation and amortization	5	6	18	20
Real Estate Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	6	29	17	49
Other revenues from operations	23	22	59	58
Interest and dividend income	1		1
Other income (loss), net				1
Total revenues	30	51	77	108
Cost of goods sold	5	20	13	34
Other expenses from operations	18	17	50	48
Selling, general and administrative	5	4	14	13
Total Expenses	28	41	77	95
Pre-tax loss	2	10		13
Net (loss) income	2	10		13
Net income (loss) attributable to Icahn Enterprises	2	10		13
Capital expenditures	6		15	2
Depreciation and amortization	3	4	10	10
Home Fashion Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	47	46	127	132
Other income (loss), net	(3)	1	(3)	1
Total revenues	44	47	124	133
Cost of goods sold	38	37	98	104
Selling, general and administrative	10	9	31	29
Restructuring, net		1		1
Interest expense	1	1	1	1
Total Expenses	49	48	130	135
Pre-tax loss	(5)	(1)	(6)	(2)
Net (loss) income	(5)	(1)	(6)	(2)
Net income (loss) attributable to Icahn Enterprises	(5)	(1)	(6)	(2)
Capital expenditures	1	1	3	2
Depreciation and amortization	2	2	5	5
Pharma
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Net sales	27	25	76	68
Other revenues from operations	1	1	3	3
Interest and dividend income			1
Other income (loss), net	1		1	1
Total revenues	29	26	81	72
Cost of goods sold	13	15	41	41
Selling, general and administrative	12	11	32	35
Total Expenses	25	26	73	76
Pre-tax loss	4		8	(4)
Net (loss) income	4		8	(4)
Net income (loss) attributable to Icahn Enterprises	4		8	(4)
Depreciation and amortization	7	7	21	21
Holding Company
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Interest and dividend income	26	24	76	71
Other income (loss), net	8		8
Total revenues	34	24	84	71
Selling, general and administrative	9	9	23	24
Credit loss on related party note receivable		23		139
Loss on deconsolidation of subsidiary				246
Interest expense	80	71	234	214
Total Expenses	89	103	257	623
Pre-tax loss	(55)	(79)	(173)	(552)
Income tax (expense) benefit	(4)	(12)	(34)	90
Net (loss) income	(59)	(91)	(207)	(462)
Net income (loss) attributable to Icahn Enterprises	$ (59)	(91)	$ (207)	(462)
Depreciation and amortization		$ 1		$ 1