POST-EMPLOYMENT BENEFITS - Fair Value of Plan Assets (Details) $ in Millions	Dec. 31, 2017 USD ($)
Disclosure of fair value of plan assets [line items]
Cash and cash equivalents	$ 2
Equity instruments	19
Debt instruments	92
Investment funds	0
Fixed insurance contracts	13
Total plan assets	126
Level 1
Disclosure of fair value of plan assets [line items]
Cash and cash equivalents	2
Equity instruments	1
Debt instruments	2
Investment funds	0
Fixed insurance contracts	0
Total plan assets	5
Level 2
Disclosure of fair value of plan assets [line items]
Cash and cash equivalents	0
Equity instruments	18
Debt instruments	90
Investment funds	0
Fixed insurance contracts	0
Total plan assets	108
Level 3
Disclosure of fair value of plan assets [line items]
Cash and cash equivalents	0
Equity instruments	0
Debt instruments	0
Investment funds	0
Fixed insurance contracts	13
Total plan assets	$ 13

Fixed Insurance Contracts, Amount Contributed To Fair Value Of Plan Assets

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- Definition

The amount that cash and cash equivalents constitute of the fair value of defined benefit plan assets. [Refer: Cash and cash equivalents; Plan assets, at fair value; Defined benefit plans [member]]

+ References

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- Definition

The amount that instruments representing debt (rather than equity) constitute of the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]]

+ References

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

+ References

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- Definition

The amount that instruments representing equity (rather than debt) constitute of the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]]

+ References

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- Definition

The amount that investment funds constitute of the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]; Investment funds [member]]

+ References

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- Definition

The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

+ References

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