Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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No definition available.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Share-based compensation - Restricted shares (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020
Restricted shares
Total share-based compensation expense	$ 1,319	$ 905	$ 3,440	$ 1,181
Restricted ordinary shares
Number of shares
Unvested restricted ordinary shares at beginning			0
Unvested restricted ordinary shares at ending	0		0
Restricted shares
Unvested restricted ordinary shares	0		0		0
Total share-based compensation expense	$ 0	300	$ 0	400
Restricted ordinary shares \| Employees and directors
Restricted shares
Unrecognized compensation cost					$ 0
Restricted ordinary shares \| Employee
Restricted shares
Fair value of employee restricted share awards vested	$ 0	$ 600	$ 0	$ 700