Long-Term Employee Benefit Liabilities - Future Benefit Payments (Detail) $ in Millions	Dec. 31, 2017 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions - 2018	$ 31
2018	35
2019	36
2020	40
2021	42
2022	46
Thereafter	251
Total	450
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions - 2018	19
2018	23
2019	23
2020	24
2021	25
2022	26
Thereafter	143
Total	264
Termination and Long Service Arrangements [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions - 2018	10
2018	10
2019	11
2020	14
2021	15
2022	18
Thereafter	99
Total	167
Retirement Medical Benefits Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions - 2018	2
2018	2
2019	2
2020	2
2021	2
2022	2
Thereafter	9
Total	$ 19

Defined benefit plan expected aggregate future benefit payments.

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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.

+ References

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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