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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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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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		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Restricted shares
Total share-based compensation expense	$ 1,510	$ 819	$ 4,950	$ 2,000
Restricted ordinary shares
Restricted shares
Unvested restricted ordinary shares	0		0		0
Total share-based compensation expense	$ 0	0	$ 0	400
Restricted ordinary shares \| Employees and directors
Restricted shares
Unrecognized compensation cost	0		0
Restricted ordinary shares \| Employee
Restricted shares
Fair value of employee restricted share awards vested	$ 0	$ 0	$ 0	$ 700