FAIR VALUE MEASUREMENTS - Reconciliation of level 3 defined benefit plan assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Insurance contract
Change in plan assets:
Fair value of plan assets, January 1	$ 110	$ 0
Purchase of insurance contract		106
Delphi Technologies acquisition	0
Purchases, sales and settlements	0
Realized gains	0
Benefits paid	(6)
Unrealized gains (losses) on assets still held at the reporting date	6	2
Translation adjustment	3	2
Fair value of plan assets, December 31	113	110
Real estate trust fund
Change in plan assets:
Fair value of plan assets, January 1	0	0
Purchase of insurance contract		0
Delphi Technologies acquisition	82
Purchases, sales and settlements	0
Realized gains	0
Benefits paid	0
Unrealized gains (losses) on assets still held at the reporting date	(2)	0
Translation adjustment	6	0
Fair value of plan assets, December 31	86	0
Hedge funds
Change in plan assets:
Fair value of plan assets, January 1	0	0
Purchase of insurance contract		0
Delphi Technologies acquisition	103
Purchases, sales and settlements	(114)
Realized gains	3
Benefits paid	0
Unrealized gains (losses) on assets still held at the reporting date	0	0
Translation adjustment	8	0
Fair value of plan assets, December 31	$ 0	$ 0

Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Benefits Paid

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- Definition

Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase For Business Acquisition

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- Definition

Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Realized Gains

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- Definition

Level 3 reconciliation, translation adjustment

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

Amount, measured using unobservable input, of increase in plan asset of defined benefit plan from purchase.

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- Definition

Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.

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