Condensed Balance Sheets By Reporting Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 1,876	$ 2,868	$ 2,078	$ 2,912
Cash held at consolidated affiliated partnerships and restricted cash	751		1,282
Investments	10,026		15,351
Accounts receivable, net	1,839		1,685
Inventories, net	2,896		2,259
Property, plant and equipment, net	10,572		9,535
Goodwill and intangible assets, net	2,406		2,612
Other assets	1,916		1,601
Total assets	32,282		36,403
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	6,252		4,441
Securities sold, not yet purchased, at fair value	1,052		794
Due to brokers	2,710		7,317
Post-employment benefit liability	1,230		1,224
Debt	12,530		12,594
Total assets	23,774		26,370
Equity attributable to Icahn Enterprises	2,516		3,987
Equity attributable to non-controlling interests	5,992		6,046
Total equity	8,508	12,735	10,033	12,390
Total liabilities and equity	32,282		36,403
Interest expense	241	270
Net (loss) income	(1,609)	422
Net (loss) income attributable to Icahn Enterprises	(837)	161
Investment Segment [Member]
ASSETS
Cash and cash equivalents	12		10
Cash held at consolidated affiliated partnerships and restricted cash	663		1,199
Investments	9,271		14,553
Accounts receivable, net	0		0
Inventories, net	0		0
Property, plant and equipment, net	0		0
Goodwill and intangible assets, net	0		0
Other assets	630		378
Total assets	10,576		16,140
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	924		488
Securities sold, not yet purchased, at fair value	1,052		794
Due to brokers	2,710		7,317
Post-employment benefit liability	0		0
Debt	0		0
Total assets	4,686		8,599
Equity attributable to Icahn Enterprises	1,820		3,428
Equity attributable to non-controlling interests	4,070		4,113
Total equity	5,890		7,541
Total liabilities and equity	10,576		16,140
Interest expense	87	123
Net (loss) income	(983)	396
Net (loss) income attributable to Icahn Enterprises	(450)	184
Automotive Segment [Member]
ASSETS
Cash and cash equivalents	309		201
Cash held at consolidated affiliated partnerships and restricted cash	4		0
Investments	313		296
Accounts receivable, net	1,546		1,418
Inventories, net	2,342		1,656
Property, plant and equipment, net	3,281		2,386
Goodwill and intangible assets, net	1,915		1,556
Other assets	576		430
Total assets	10,286		7,943
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	3,000		2,061
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	1,169		1,163
Debt	3,282		3,135
Total assets	7,451		6,359
Equity attributable to Icahn Enterprises	2,502		1,270
Equity attributable to non-controlling interests	333		314
Total equity	2,835		1,584
Total liabilities and equity	10,286		7,943
Interest expense	39	36
Net (loss) income	28	(20)
Net (loss) income attributable to Icahn Enterprises	21	(18)
Energy Segment [Member]
ASSETS
Cash and cash equivalents	682		765
Cash held at consolidated affiliated partnerships and restricted cash	0		0
Investments	5		0
Accounts receivable, net	110		96
Inventories, net	259		290
Property, plant and equipment, net	2,692		2,698
Goodwill and intangible assets, net	332		911
Other assets	103		128
Total assets	4,183		4,888
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	1,327		1,366
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	0		0
Debt	668		667
Total assets	1,995		2,033
Equity attributable to Icahn Enterprises	1,119		1,508
Equity attributable to non-controlling interests	1,069		1,347
Total equity	2,188		2,855
Total liabilities and equity	4,183		4,888
Interest expense	11	12
Net (loss) income	(614)	75
Net (loss) income attributable to Icahn Enterprises	(353)	43
Metals Segment [Member]
ASSETS
Cash and cash equivalents	6		12
Cash held at consolidated affiliated partnerships and restricted cash	5		4
Investments	0		0
Accounts receivable, net	27		26
Inventories, net	39		39
Property, plant and equipment, net	112		116
Goodwill and intangible assets, net	4		5
Other assets	13		13
Total assets	206		215
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	30		30
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	2		2
Debt	0		1
Total assets	32		33
Equity attributable to Icahn Enterprises	174		182
Equity attributable to non-controlling interests	0		0
Total equity	174		182
Total liabilities and equity	206		215
Interest expense	0	0
Net (loss) income	(6)	(9)
Net (loss) income attributable to Icahn Enterprises	(6)	(9)
Railcar Segment [Member]
ASSETS
Cash and cash equivalents	346		623
Cash held at consolidated affiliated partnerships and restricted cash	52		53
Investments	27		27
Accounts receivable, net	34		36
Inventories, net	76		97
Property, plant and equipment, net	2,772		2,767
Goodwill and intangible assets, net	7		7
Other assets	88		71
Total assets	3,402		3,681
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	297		299
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	8		8
Debt	2,461		2,671
Total assets	2,766		2,978
Equity attributable to Icahn Enterprises	423		742
Equity attributable to non-controlling interests	213		(39)
Total equity	636		703
Total liabilities and equity	3,402		3,681
Interest expense	23	20
Net (loss) income	50	44
Net (loss) income attributable to Icahn Enterprises	36	27
Gaming Segment [Member]
ASSETS
Cash and cash equivalents	251		217
Cash held at consolidated affiliated partnerships and restricted cash	11		14
Investments	42		26
Accounts receivable, net	12		9
Inventories, net	0		0
Property, plant and equipment, net	886		740
Goodwill and intangible assets, net	91		74
Other assets	221		201
Total assets	1,514		1,281
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	143		118
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	0		0
Debt	288		289
Total assets	431		407
Equity attributable to Icahn Enterprises	816		604
Equity attributable to non-controlling interests	267		270
Total equity	1,083		874
Total liabilities and equity	1,514		1,281
Interest expense	3	3
Net (loss) income	6	7
Net (loss) income attributable to Icahn Enterprises	3	5
Mining segment [Member]
ASSETS
Cash and cash equivalents	5		14
Cash held at consolidated affiliated partnerships and restricted cash	0		0
Investments	0		0
Accounts receivable, net	3		4
Inventories, net	29		32
Property, plant and equipment, net	135		134
Goodwill and intangible assets, net	0		0
Other assets	20		19
Total assets	192		203
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	32		30
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	0		0
Debt	50		50
Total assets	82		80
Equity attributable to Icahn Enterprises	85		95
Equity attributable to non-controlling interests	25		28
Total equity	110		123
Total liabilities and equity	192		203
Interest expense	1	0
Net (loss) income	(13)	0
Net (loss) income attributable to Icahn Enterprises	(10)	0
Food Packaging Segment [Member]
ASSETS
Cash and cash equivalents	37		37
Cash held at consolidated affiliated partnerships and restricted cash	2		1
Investments	0		0
Accounts receivable, net	62		60
Inventories, net	80		77
Property, plant and equipment, net	152		152
Goodwill and intangible assets, net	8		8
Other assets	85		81
Total assets	426		416
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	64		62
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	51		51
Debt	267		267
Total assets	382		380
Equity attributable to Icahn Enterprises	29		23
Equity attributable to non-controlling interests	15		13
Total equity	44		36
Total liabilities and equity	426		416
Interest expense	3	3
Net (loss) income	4	0
Net (loss) income attributable to Icahn Enterprises	3	0
Real Estate Segment [Member]
ASSETS
Cash and cash equivalents	11		19
Cash held at consolidated affiliated partnerships and restricted cash	2		2
Investments	0		0
Accounts receivable, net	3		2
Inventories, net	0		0
Property, plant and equipment, net	467		467
Goodwill and intangible assets, net	46		48
Other assets	161		163
Total assets	690		701
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	14		17
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	0		0
Debt	27		28
Total assets	41		45
Equity attributable to Icahn Enterprises	649		656
Equity attributable to non-controlling interests	0		0
Total equity	649		656
Total liabilities and equity	690		701
Interest expense	1	1
Net (loss) income	4	23
Net (loss) income attributable to Icahn Enterprises	4	23
Home Fashion Segment [Member]
ASSETS
Cash and cash equivalents	5		14
Cash held at consolidated affiliated partnerships and restricted cash	9		6
Investments	0		0
Accounts receivable, net	42		34
Inventories, net	71		68
Property, plant and equipment, net	72		72
Goodwill and intangible assets, net	3		3
Other assets	6		9
Total assets	208		206
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	33		30
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	0		0
Debt	0		0
Total assets	33		30
Equity attributable to Icahn Enterprises	175		176
Equity attributable to non-controlling interests	0		0
Total equity	175		176
Total liabilities and equity	208		206
Interest expense	0	0
Net (loss) income	0	(1)
Net (loss) income attributable to Icahn Enterprises	0	(1)
Holding Company [Member]
ASSETS
Cash and cash equivalents	212		166
Cash held at consolidated affiliated partnerships and restricted cash	3		3
Investments	368		449
Accounts receivable, net	0		0
Inventories, net	0		0
Property, plant and equipment, net	3		3
Goodwill and intangible assets, net	0		0
Other assets	13		108
Total assets	599		729
LIABILITIES AND EQUITY
Accounts payable, accrued expenses and other liabilities	388		(60)
Securities sold, not yet purchased, at fair value	0		0
Due to brokers	0		0
Post-employment benefit liability	0		0
Debt	5,487		5,486
Total assets	5,875		5,426
Equity attributable to Icahn Enterprises	(5,276)		(4,697)
Equity attributable to non-controlling interests	0		0
Total equity	(5,276)		(4,697)
Total liabilities and equity	599		729
Interest expense	73	72
Net (loss) income	(85)	(93)
Net (loss) income attributable to Icahn Enterprises	(85)	(93)
Holding Company [Member]
ASSETS
Cash and cash equivalents	1,876	2,868	2,078	2,912
Cash held at consolidated affiliated partnerships and restricted cash	751		1,282
Investments	10,026		15,351
Accounts receivable, net	1,839		1,685
Inventories, net	2,896		2,259
Property, plant and equipment, net	10,572		9,535
Total assets	32,306		36,427
LIABILITIES AND EQUITY
Securities sold, not yet purchased, at fair value	1,052		794
Due to brokers	2,710		7,317
Post-employment benefit liability	1,230		1,224
Debt	12,530		12,594
Total assets	23,774		26,370
Equity attributable to Icahn Enterprises	2,540		4,011
Equity attributable to non-controlling interests	5,992		6,046
Total equity	8,532	12,758	10,057	$ 12,413
Total liabilities and equity	32,306		36,427
Interest expense	241	270
Net (loss) income	(1,609)	422
Net (loss) income attributable to Icahn Enterprises	(837)	161
Holding Company [Member] | Investment Segment [Member]
ASSETS
Total assets	10,576		16,140
LIABILITIES AND EQUITY
Interest expense	87	123
Net (loss) income	(983)	396
Net (loss) income attributable to Icahn Enterprises	(450)	184
Holding Company [Member] | Automotive Segment [Member]
ASSETS
Total assets	10,286		7,943
LIABILITIES AND EQUITY
Interest expense	39	36
Net (loss) income	28	(20)
Net (loss) income attributable to Icahn Enterprises	21	(18)
Holding Company [Member] | Energy Segment [Member]
ASSETS
Total assets	4,183		4,888
LIABILITIES AND EQUITY
Interest expense	11	12
Net (loss) income	(614)	75
Net (loss) income attributable to Icahn Enterprises	(353)	43
Holding Company [Member] | Metals Segment [Member]
ASSETS
Total assets	206		215
LIABILITIES AND EQUITY
Interest expense	0	0
Net (loss) income	(6)	(9)
Net (loss) income attributable to Icahn Enterprises	(6)	(9)
Holding Company [Member] | Railcar Segment [Member]
ASSETS
Total assets	3,402		3,681
LIABILITIES AND EQUITY
Interest expense	23	20
Net (loss) income	50	44
Net (loss) income attributable to Icahn Enterprises	36	27
Holding Company [Member] | Gaming Segment [Member]
ASSETS
Total assets	1,514		1,281
LIABILITIES AND EQUITY
Interest expense	3	3
Net (loss) income	6	7
Net (loss) income attributable to Icahn Enterprises	3	5
Holding Company [Member] | Mining segment [Member]
ASSETS
Total assets	192		203
LIABILITIES AND EQUITY
Interest expense	1	0
Net (loss) income	(13)	0
Net (loss) income attributable to Icahn Enterprises	(10)	0
Holding Company [Member] | Food Packaging Segment [Member]
ASSETS
Total assets	426		416
LIABILITIES AND EQUITY
Interest expense	3	3
Net (loss) income	4	0
Net (loss) income attributable to Icahn Enterprises	3	0
Holding Company [Member] | Real Estate Segment [Member]
ASSETS
Total assets	690		701
LIABILITIES AND EQUITY
Interest expense	1	1
Net (loss) income	4	23
Net (loss) income attributable to Icahn Enterprises	4	23
Holding Company [Member] | Home Fashion Segment [Member]
ASSETS
Total assets	208		206
LIABILITIES AND EQUITY
Interest expense	0	0
Net (loss) income	0	(1)
Net (loss) income attributable to Icahn Enterprises	0	(1)
Holding Company [Member] | Holding Company [Member]
ASSETS
Total assets	623		$ 753
LIABILITIES AND EQUITY
Interest expense	73	72
Net (loss) income	(85)	(93)
Net (loss) income attributable to Icahn Enterprises	$ (85)	$ (93)