Cash and cash equivalents - Summary of Cash and Cash Equivalents (Detail) - USD ($) $ in Millions |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Cash and cash equivalents [abstract] | ||
| Cash at bank and in hand | $ 164 | $ 131 |
| Short-term deposits | 4 | 75 |
| Cash and cash equivalents | $ 168 | $ 206 |
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- Definition The amount of cash on hand and demand deposits. [Refer: Cash on hand] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition A classification of cash equivalents representing short-term deposits. [Refer: Cash equivalents] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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