Share-based Payment Arrangements - Summary of Information About Restricted Shares (Detail)	12 Months Ended
Dec. 31, 2020 shares ¥ / shares	Dec. 31, 2019 shares ¥ / shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Options exercisable, end of year
Exercise Price Per Share, Options exercisable, end of year \| ¥ / shares
USISH option plans [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Balance at January 1	6,156,000
Options granted	672,000	6,156,000
Options exercised	(1,281,000)
Balance at December 31	5,547,000	6,156,000
Fair value of options granted (RMB)	18.55	13.47
Exercise Price Per Share, Begining \| ¥ / shares	¥ 13.3
Exercise Price Per Share, Options granted \| ¥ / shares	4.9	¥ 13.3
Exercise Price Per Share, Options exercised \| ¥ / shares	13.2
Exercise Price Per Share, Ending \| ¥ / shares	¥ 12.2	¥ 13.3

Number of other equity instruments outstanding share based payment arrangement at fair value of options granted.

No definition available.

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- 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.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 47
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard
-URIDate 2020-01-01

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard
-URIDate 2020-01-01

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- Definition

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

+ References

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

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- Definition

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

+ References

+ Details

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- Definition

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]]

+ References

+ Details

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- Definition

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

+ References

+ Details

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