Provisions - Current and non-current (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Provisions
Current	$ 70	$ 73	$ 52	$ 61
Noncurrent	44	60	52	$ 40
Total	$ 114	$ 133	$ 105

No definition available.

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- Definition

The amount of non-current provisions other than provisions for employee benefits. [Refer: Non-current provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- Definition

The amount of provisions other than provisions for employee benefits. [Refer: Provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- Definition

The amount of current provisions other than provisions for employee benefits. [Refer: Provisions]

+ References

+ Details

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