Share-based Payment - Number and Weighted Average Exercise Prices ("WAEP") of, and Movements in Share Options (Detail)	Dec. 31, 2019 shares $ / shares	Dec. 31, 2018 shares $ / shares
Disclosure of terms and conditions of share-based payment arrangement [abstract]
Number of share options outstanding \| shares	470,000	470,000
Number of share options exercisable \| shares	470,000	470,000
WAEP outstanding \| $ / shares	$ 21.11	$ 21.11
WAEP exercisable \| $ / shares	$ 21.11	$ 21.11

Weighted average exercise price of share options exercisable in share-based payment arrangement value.

No definition available.

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- References

No definition available.

+ Details

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- Definition

The number of share options outstanding in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2019-01-01
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+ Details

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- Definition

The number of share options exercisable in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2019-01-01
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- Definition

The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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