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

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- Definition

Debt Instrument, Redemption Price, Redeemable Principal Amount

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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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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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No definition available.

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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 equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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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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Face amount or stated value per share of common stock.

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- Definition

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

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Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage of principal amount of debt redeemed.

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No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, 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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- 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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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 equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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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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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Amount of unrealized gain (loss) on investment.

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ACQUISITIONS - Narrative (Details) € / shares in Units, $ / shares in Units, € in Millions					1 Months Ended	3 Months Ended
	Feb. 19, 2021 USD ($)	Feb. 15, 2021 EUR (€) € / shares	Oct. 05, 2020 USD ($)	Oct. 01, 2020 USD ($) $ / shares	Sep. 30, 2019 USD ($)	Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 29, 2020	May 31, 2019 USD ($)
Business Acquisition [Line Items]
Goodwill						$ 2,596,000,000		$ 2,627,000,000
Number of reportable segments \| segment						4
Unrealized loss on equity securities						$ 272,000,000	$ 9,000,000
Equity securities						202,000,000		$ 472,000,000
Romeo Power Inc
Business Acquisition [Line Items]
Equity method interest (percent)										20.00%
BorgWarner Romeo Power LLC
Business Acquisition [Line Items]
Payments for investments in equity securities										$ 50,000,000
Payments to acquire interest in joint venture					$ 10,000,000
Unrealized loss on equity securities						272,000,000
Equity securities						160,000,000
Asset impairment and loss on divestiture							9,000,000
Investment in equity securities							41,000,000
Senior Notes
Business Acquisition [Line Items]
Debt instrument, face amount				$ 800,000,000
Term Loan Facility
Business Acquisition [Line Items]
Debt instrument, face amount	$ 900,000,000
Debt instrument, term	364 days
AKASOL
Business Acquisition [Line Items]
Percentage of interest expected to be held		59.00%
BorgWarner Romeo Power LLC
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent (in percent)					60.00%				14.00%
DT Notes \| Senior Notes
Business Acquisition [Line Items]
Debt instrument stated interest rate				5.00%
Redeemable principal amount			$ 776,000,000
Percentage of principal amount redeemed			97.00%
AKASOL
Business Acquisition [Line Items]
Share price (in euro per share) \| € / shares		€ 120.00
Business acquisition, percentage of voting interests acquired		100.00%
Borgwarner common stock issued for purchase of delphi technologies \| €		€ 727
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
Total consideration				$ 2,391,000,000
Goodwill				710,000,000		$ 711,000,000
Net sales							$ 3,224,000,000
Delphi Technologies PLC \| Senior Notes
Business Acquisition [Line Items]
Financial liabilities assumed				$ 800,000,000
Senior notes			$ 24,000,000