The date on which share-based payment arrangements are granted. [Refer: Share-based payment arrangements [member]]

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The description of the vesting requirements for a type of share-based payment arrangement that existed at any time during the period. An entity with substantially similar types of share-based payment arrangements may aggregate this information. [Refer: Share-based payment arrangements [member]]

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The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement.

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The weighted average exercise price of other equity instruments (ie other than share options) granted in a share-based payment arrangement. [Refer: Weighted average [member]]

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The weighted average remaining contractual life of outstanding share options. [Refer: Weighted average [member]]

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Share-based Payments - Issuance of Restricted Shares (Detail) shares in Thousands	May 10, 2016 shares $ / shares	Jul. 21, 2015 shares $ / shares	Dec. 31, 2019 shares	Dec. 31, 2018 shares
Disclosure of share based payments other than equity instrument [line items]
Grant date	May 10,2016	July 21,2015
July 21, 2015 [member]
Disclosure of share based payments other than equity instrument [line items]
Number of shares returned due to employee resignation				(256)
May 10, 2016 [member]
Disclosure of share based payments other than equity instrument [line items]
Number of shares returned due to employee resignation			(25)	(116)
Restricted shares award agreement [member] \| July 21, 2015 [member]
Disclosure of share based payments other than equity instrument [line items]
Type of arrangement		Restricted shares award agreement
Share price on grant date \| $ / shares		$ 36.1
Number of shares		15,752
Contract period		3 years
Vesting condition		Meet service and performance conditions
Restricted shares award agreement [member] \| May 10, 2016 [member]
Disclosure of share based payments other than equity instrument [line items]
Type of arrangement	Restricted shares award agreement
Share price on grant date \| $ / shares	$ 30.6
Number of shares	1,548
Contract period	3 years
Vesting condition	Meet service and performance conditions