Business Combination, Consideration Transferred, Equity Interests Issued and Issuable, Fixed Exchange Ratio

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Equity Method Investment , Increase (Decrease) In Ownership Percentage

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liability recognized arising from contingent consideration in a business combination.

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The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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- Definition

Face amount or stated value per share of common stock.

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Face (par) amount of debt instrument at time of issuance.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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No definition available.

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Amount of investment in equity security without readily determinable fair value.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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The number of businesses acquired by the entity during the period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Amount of unrealized gain (loss) on investment.

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ACQUISITIONS - Narrative (Details)			3 Months Ended			12 Months Ended
ACQUISITIONS - Narrative (Details)	Oct. 01, 2020 USD ($) $ / shares	Jan. 02, 2019 USD ($) business_acquired	Dec. 31, 2020 USD ($) $ / shares	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Dec. 29, 2020	Jun. 19, 2020 USD ($)	May 31, 2019 USD ($)
Business Acquisition [Line Items]
Common stock, par value (in dollar per share) \| $ / shares			$ 0.01			$ 0.01	$ 0.01
Unrealized gain on equity securities						$ (382,000,000)	$ 0	$ 0
Equity securities			$ 472,000,000			472,000,000	60,000,000
Number of businesses acquired \| business_acquired		2
Cash consideration						449,000,000	10,000,000	0
Goodwill			2,627,000,000			2,627,000,000	1,842,000,000
Senior Notes
Business Acquisition [Line Items]
Debt instrument face value										$ 1,100,000,000
e-Propulsion & Drivetrain
Business Acquisition [Line Items]
Goodwill			1,313,000,000			1,313,000,000	$ 1,007,000,000	$ 1,012,000,000
Corporate Joint Venture \| BorgWarner Romeo Power LLC
Business Acquisition [Line Items]
Noncontrolling interest											60.00%
Romeo Power Inc.
Business Acquisition [Line Items]
Ownership interest equity interest							20.00%				20.00%
Asset impairment				$ 9,000,000
Investment in equity securities				41,000,000
Equity method investment , increase (Decrease) In ownership percentage									14.00%
Unrealized gain on equity securities			(391,000,000)
Equity securities			432,000,000			432,000,000
BorgWarner Romeo Power LLC \| Corporate Joint Venture
Business Acquisition [Line Items]
Equity securities without readily determinable fair value											$ 10,000,000
Delphi Technologies PLC
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	100.00%
Fixed exchange ratio	0.4307
Common stock, par value (in dollar per share) \| $ / shares	$ 0.01
Business combination, consideration transferred	$ 2,391,000,000
Acquisition related costs						89,000,000
Cash consideration	18,000,000
Goodwill	760,000,000
Goodwill	710,000,000
Delphi Technologies PLC \| Senior Notes
Business Acquisition [Line Items]
Financial liabilities assumed	$ 800,000,000
Romeo Power Inc.
Business Acquisition [Line Items]
Equity securities without readily determinable fair value											$ 50,000,000
Rinehart Motion Systems LLC and AM Racing LLC
Business Acquisition [Line Items]
Business combination, consideration transferred		$ 15,000,000
Cash consideration				$ 2,000,000	$ 10,000,000
Business combination, contingent consideration, liability			$ 3,000,000			$ 3,000,000
Reporting segment and other assets and liabilities		$ 2,000,000
Rinehart Motion Systems LLC and AM Racing LLC \| Minimum
Business Acquisition [Line Items]
Estimated life		2 years
Rinehart Motion Systems LLC and AM Racing LLC \| Maximum
Business Acquisition [Line Items]
Estimated life		15 years
Rinehart Motion Systems LLC and AM Racing LLC \| e-Propulsion & Drivetrain
Business Acquisition [Line Items]
Goodwill		$ 5,000,000
Goodwill		$ 7,000,000