Taxation - Gross movement on the deferred income tax account (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Changes in deferred tax liability (asset) [abstract]
Deferred tax liability (asset), beginning balance	$ 23,897	$ 53,108
Exchange differences	(1,695)	10,953
Tax charge relating to cash flow hedge	(8,715)	(52,282)
Income tax benefit	19,493	12,118	$ 10,117
Deferred tax liability (asset), ending balance	$ 32,980	$ 23,897	$ 53,108

No definition available.

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- Definition

The amount of tax expense (income) relating to changes in deferred tax liabilities and deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities]

+ References

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+ Details

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- Definition

The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets]

+ References

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income]

+ References

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- Definition

The increase (decrease) in deferred tax liability (asset) resulting from the net exchange differences arising when the financial statements are translated from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Deferred tax liability (asset)]

+ References

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