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Principal accounting policies (Table) | 12 Months Ended
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Dec. 31, 2018
Disclosure Of Accounting Policies [Abstract] |
Summary of significant differences between lease commitments and lease liability recorded on transition |
| US$bn
Operating lease commitments under IAS 17 per note 31 | 1.7
Exclude/deduct |
Leases expiring in 12 months or fewer (a) | (0.1)
Committed leases not commenced (a) | (0.1)
Components excluded from the lease liability (a) | (0.2)
Include/add |
Cost of reasonably certain extensions (a) | 0.3
Other (b) | 0.1
Sub total | 1.7
Effect of discounting on payments included in the calculation of the lease liability (excluding finance lease balances) | (0.4)
Lease liability opening balance reported as at 1 January 2019 (IFRS 16) | 1.3
(a)Undiscounted. (b)Includes finance lease liabilities already reported under IAS 17. Refer to note 23.

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