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Share-based Payment Arrangements - Summary of USISH's outstanding share options balance sheet (Detail) - USISH Option Plans [member] - ¥ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share options [Member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	¥ 15.5	¥ 15.5
Weighted average remaining contractual life of outstanding share options	5 years 10 months 24 days	6 years 10 months 24 days
Stock option plans [Member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	¥ 13.3
Weighted average remaining contractual life of outstanding share options	4 years 10 months 24 days
Core Employees Stock Ownership Plan [Member]
Disclosure of range of exercise prices of outstanding share options [Line Items]
Range of Exercise Price Per Share	¥ 13.3
Weighted average remaining contractual life of outstanding share options	4 years 3 months 18 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 2019-01-01
-Paragraph 45
-Subparagraph d
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-URIDate 2019-03-27

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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 2019-01-01
-Paragraph 45
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-URIDate 2019-03-27

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