Share-based payments (Tables)

6 Months Ended

Jun. 30, 2018

Share-Based Payment Arrangements [Abstract]

Disclosure of detail as to expenses recorded within the profit and loss with respect to the LTIP

The following table details the costs charged to the income statement with respect to the 2015 Plan, 2016 Plan and 2017 Plan.

	USD k
	For the Six Months Ended Jun 30,
	2018	2017
Expense arising from equity-settled share based payment transactions (2015 Plan)	777	1,241
Expense arising from equity-settled share based payment transactions (2016 Plan)	2,253	1,968
Expense arising from equity-settled share based payment transactions (2017 Plan)	2,360	—
Expenses arising form equity-settled share based 2018 incentive	563	—
Total expenses	5,953	3,209

Disclosure of the number of and movements in PSUs

The following table illustrates the number of, and movements in, performance share units ("PSUs") during the period.

	2015 Plan				2016 Plan				2017 Plan			Total
	Number of PSUs				Number of PSUs				Number of PSUs			Number of PSUs
	2018		2017		2018		2017		2018		2017	2018		2017
Outstanding at January 1,	452,816		454,959		686,038		690,279		472,040			1,610,894		1,145,238
Granted during the period	—		—		113		—		830			943		—
Forfeited during the period	(5,694	)	(1,515	)	(8,544	)	(4,241	)	(5,521	)		(19,759	)	(5,756	)
Vested during the period	(447,122	)	—		—		—		—			(447,122	)	—
Outstanding at June 30,	—		453,444		677,607		686,038		467,349		—	1,144,956		1,139,482

Disclosure of indirect measurement of fair value of goods or services received, other equity instruments granted during period

The following table lists the inputs to the model used for the grant date fair values of the 2015 Plan, 2016 Plan and 2017 Plan.

	2015 Plan	2016 Plan	2017 Plan
Dividend Yield (%)	2.14%	2.23%	1.88%
Expected Volatility OEC (%)	25.16%	32.07%	33.77%
Expected Volatility Peer Group (%)	13.90%	18.12%	17.30%
Correlation	0.5234	0.4952	0.4574
Risk-free interest rate (%)	0.90%	0.76%	1.45%
Model used	Monte Carlo	Monte Carlo	Monte Carlo
Weighted average fair value of PSUs granted in USD	17.41	17.21	24.89