Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2020
Accounting Policies [Abstract]
Consolidation, Policy	Current Economic Conditions In March 2020, the World Health Organization categorized COVID-19 as a pandemic and the President of the United States declared the COVID-19 outbreak a national emergency. The COVID-19 pandemic, and actions taken by governments and others in response thereto, has negatively impacted the global economy, financial markets, and the industries in which our subsidiaries operate. Our consolidated results of operations and financial condition have been impacted primarily by the net declines in fair value of investments held by our Investment segment and the Holding Company (primarily unrealized) as well as declines in the global demand for refined products, especially gasoline, with respect to our Energy segment. The impact on our businesses has also included the acceleration of selective planned store closures in our Automotive segment, lowering current year forecasts across various segments and recording write-downs to inventories. We believe that the current economic conditions will continue to impact our businesses through at least the first half of 2020, and likely through the remainder of the year. The extent and duration of impact on our future results of operations, liquidity and financial condition is uncertain and may be significant. Principles of Consolidation As of March 31, 2020, our condensed consolidated financial statements include the accounts of (i) Icahn Enterprises and Icahn Enterprises Holdings and (ii) the wholly and majority owned subsidiaries of Icahn Enterprises and Icahn Enterprises Holdings, in addition to variable interest entities (“VIEs”) in which we are the primary beneficiary. In evaluating whether we have a controlling financial interest in entities that we consolidate, we consider the following: (1) for voting interest entities, including limited partnerships and similar entities that are not VIEs, we consolidate these entities in which we own a majority of the voting interests; and (2) for VIEs, we consolidate these entities in which we are the primary beneficiary. See below for a discussion of our VIEs. Kick-out rights, which are the rights underlying the limited partners’ ability to dissolve the limited partnership or otherwise remove the general partners, held through voting interests of partnerships and similar entities that are not VIEs are considered the equivalent of the equity interests of corporations that are not VIEs. Except for our Investment segment and Holding Company, for equity investments in which we own 50% or less but greater than 20%, we generally account for such investments using the equity method. All other equity investments are accounted for at fair value.
Reclassifications [Text Block]	Reclassifications Certain reclassifications from the prior year presentation have been made to conform to the current year presentation, which did not have an impact on previously reported net income and equity and are not deemed material.
Consolidation, Variable Interest Entity, Policy [Policy Text Block]	Consolidated Variable Interest Entities The following is a discussion of variable interest entities in which we are deemed to be the primary beneficiary and in which we therefore consolidate. In addition, as discussed in Note 3, “Related Party Transactions,” we have a variable interest in an entity in which we are not the primary beneficiary and therefore we do not consolidate. Icahn Enterprises Holdings We determined that Icahn Enterprises Holdings is a VIE because it is a limited partnership that lacks both substantive kick-out and participating rights. Although Icahn Enterprises is not the general partner of Icahn Enterprises Holdings, Icahn Enterprises is deemed to be the primary beneficiary of Icahn Enterprises Holdings principally based on its 99% limited partner interest in Icahn Enterprises Holdings, as well as our related party relationship with the general partner, and therefore continues to consolidate Icahn Enterprises Holdings. The condensed consolidated financial statements of Icahn Enterprises Holdings are included in this Report. The balances with respect to Icahn Enterprises Holdings’ consolidated VIEs are discussed below, comprising the Investment Funds, CVR Partners and Viskase’s joint venture. Investment We determined that each of the Investment Funds are considered VIEs because these limited partnerships lack both substantive kick-out and participating rights. Because we have a general partner interest in each of the Investment Funds and have significant limited partner interests in each of the Investment Funds, coupled with our significant exposure to losses and benefits in each of the Investment Funds, we are the primary beneficiary of each of the Investment Funds and therefore continue to consolidate each of the Investment Funds. Energy CVR Partners is considered a VIE because it is a limited partnership that lacks both substantive kick-out and participating rights. In addition, CVR Energy also concluded that, based upon its general partner’s roles and rights in CVR Partners as afforded by CVR Partners’ partnership agreement, coupled with its exposure to losses and benefits in CVR Partners through its significant limited partner interest, intercompany credit facilities and services agreements, it is the primary beneficiary of CVR Partners. Food Packaging Viskase holds a variable interest in a joint venture for which Viskase is the primary beneficiary. Viskase’s interest in the joint venture includes a 50% equity interest and also relates to the sales, operations, administrative and financial support to the joint venture through providing many of the assets used in its business.
Fair Value of Financial Instruments, Policy	Fair Value of Financial Instruments The carrying values of cash and cash equivalents, cash held at consolidated affiliated partnerships and restricted cash, accounts receivable, due from brokers, accounts payable, accrued expenses and other liabilities and due to brokers are deemed to be reasonable estimates of their fair values because of their short-term nature. See Note 4, “Investments,” and Note 5, “Fair Value Measurements,” for a detailed discussion of our investments and other non-financial assets and/or liabilities.
Statement of cash flow, policy [Policy Text Block]	Cash Flow Cash and cash equivalents and restricted cash and restricted cash equivalents on our condensed consolidated statements of cash flows is comprised of (i) cash and cash equivalents and (ii) cash held at consolidated affiliated partnerships and restricted cash.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]	Cash Held at Consolidated Affiliated Partnerships and Restricted Cash Our cash held at consolidated affiliated partnerships balance was $235 million and $86 million as of March 31, 2020 and December 31, 2019, respectively. Cash held at consolidated affiliated partnerships relates to our Investment segment and consists of cash and cash equivalents held by the Investment Funds that, although not legally restricted, are not available to fund the general liquidity needs of the Investment segment or Icahn Enterprises. Our restricted cash balance was $641 million and $1,065 million as of March 31, 2020 and December 31, 2019, respectively. Restricted cash primarily relates to our Investment segment’s cash pledged and held for margin requirements on derivative transactions.

Basis of Presentation and Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2020

Current Economic Conditions

In March 2020, the World Health Organization categorized COVID-19 as a pandemic and the President of the United States declared the COVID-19 outbreak a national emergency. The COVID-19 pandemic, and actions taken by governments and others in response thereto, has negatively impacted the global economy, financial markets, and the

industries in which our subsidiaries operate. Our consolidated results of operations and financial condition have been impacted primarily by the net declines in fair value of investments held by our Investment segment and the Holding Company (primarily unrealized) as well as declines in the global demand for refined products, especially gasoline, with respect to our Energy segment. The impact on our businesses has also included the acceleration of selective planned store closures in our Automotive segment, lowering current year forecasts across various segments and recording write-downs to inventories. We believe that the current economic conditions will continue to impact our businesses through at least the first half of 2020, and likely through the remainder of the year. The extent and duration of impact on our future results of operations, liquidity and financial condition is uncertain and may be significant.

Principles of Consolidation

As of March 31, 2020, our condensed consolidated financial statements include the accounts of (i) Icahn Enterprises and Icahn Enterprises Holdings and (ii) the wholly and majority owned subsidiaries of Icahn Enterprises and Icahn Enterprises Holdings, in addition to variable interest entities (“VIEs”) in which we are the primary beneficiary. In evaluating whether we have a controlling financial interest in entities that we consolidate, we consider the following: (1) for voting interest entities, including limited partnerships and similar entities that are not VIEs, we consolidate these entities in which we own a majority of the voting interests; and (2) for VIEs, we consolidate these entities in which we are the primary beneficiary. See below for a discussion of our VIEs. Kick-out rights, which are the rights underlying the limited partners’ ability to dissolve the limited partnership or otherwise remove the general partners, held through voting interests of partnerships and similar entities that are not VIEs are considered the equivalent of the equity interests of corporations that are not VIEs.

Except for our Investment segment and Holding Company, for equity investments in which we own 50% or less but greater than 20%, we generally account for such investments using the equity method. All other equity investments are accounted for at fair value.

Reclassifications [Text Block]

Reclassifications

Certain reclassifications from the prior year presentation have been made to conform to the current year presentation, which did not have an impact on previously reported net income and equity and are not deemed material.

Consolidation, Variable Interest Entity, Policy [Policy Text Block]

Consolidated Variable Interest Entities

The following is a discussion of variable interest entities in which we are deemed to be the primary beneficiary and in which we therefore consolidate. In addition, as discussed in Note 3, “Related Party Transactions,” we have a variable interest in an entity in which we are not the primary beneficiary and therefore we do not consolidate.

Icahn Enterprises Holdings

We determined that Icahn Enterprises Holdings is a VIE because it is a limited partnership that lacks both substantive kick-out and participating rights. Although Icahn Enterprises is not the general partner of Icahn Enterprises Holdings, Icahn Enterprises is deemed to be the primary beneficiary of Icahn Enterprises Holdings principally based on its 99% limited partner interest in Icahn Enterprises Holdings, as well as our related party relationship with the general partner, and therefore continues to consolidate Icahn Enterprises Holdings. The condensed consolidated financial statements of Icahn Enterprises Holdings are included in this Report. The balances with respect to Icahn Enterprises Holdings’ consolidated VIEs are discussed below, comprising the Investment Funds, CVR Partners and Viskase’s joint venture.

Investment

We determined that each of the Investment Funds are considered VIEs because these limited partnerships lack both substantive kick-out and participating rights. Because we have a general partner interest in each of the Investment Funds and have significant limited partner interests in each of the Investment Funds, coupled with our significant exposure to losses and benefits in each of the Investment Funds, we are the primary beneficiary of each of the Investment Funds and therefore continue to consolidate each of the Investment Funds.

Energy

CVR Partners is considered a VIE because it is a limited partnership that lacks both substantive kick-out and participating rights. In addition, CVR Energy also concluded that, based upon its general partner’s roles and rights in CVR Partners as afforded by CVR Partners’ partnership agreement, coupled with its exposure to losses and benefits in CVR Partners through its significant limited partner interest, intercompany credit facilities and services agreements, it is the primary beneficiary of CVR Partners.

Food Packaging

Viskase holds a variable interest in a joint venture for which Viskase is the primary beneficiary. Viskase’s interest in the joint venture includes a 50% equity interest and also relates to the sales, operations, administrative and financial support to the joint venture through providing many of the assets used in its business.

Fair Value of Financial Instruments, Policy

Fair Value of Financial Instruments

The carrying values of cash and cash equivalents, cash held at consolidated affiliated partnerships and restricted cash, accounts receivable, due from brokers, accounts payable, accrued expenses and other liabilities and due to brokers are deemed to be reasonable estimates of their fair values because of their short-term nature. See Note 4, “Investments,” and Note 5, “Fair Value Measurements,” for a detailed discussion of our investments and other non-financial assets and/or liabilities.

Statement of cash flow, policy [Policy Text Block]

Cash Flow

Cash and cash equivalents and restricted cash and restricted cash equivalents on our condensed consolidated statements of cash flows is comprised of (i) cash and cash equivalents and (ii) cash held at consolidated affiliated partnerships and restricted cash.

Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]

Cash Held at Consolidated Affiliated Partnerships and Restricted Cash

Our cash held at consolidated affiliated partnerships balance was $235 million and $86 million as of March 31, 2020 and December 31, 2019, respectively. Cash held at consolidated affiliated partnerships relates to our Investment segment and consists of cash and cash equivalents held by the Investment Funds that, although not legally restricted, are not available to fund the general liquidity needs of the Investment segment or Icahn Enterprises.

Our restricted cash balance was $641 million and $1,065 million as of March 31, 2020 and December 31, 2019, respectively. Restricted cash primarily relates to our Investment segment’s cash pledged and held for margin requirements on derivative transactions.