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Share-based Payment Arrangements - Summary of USIE Option Plans Outstanding Share Options (Detail) - USIE option plans [member]	12 Months Ended
	Dec. 31, 2019 $ / shares
First share options exercise price [member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	$ 1.5
Weighted Average Remaining Contractual Life (Years)	1 year
Third share options exercise price [member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	$ 2.9
Weighted Average Remaining Contractual Life (Years)	1 year 4 months 24 days

X

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The exercise price of outstanding share options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph d
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-URIDate 2020-01-01

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
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