Share-based Payment Arrangements - Summary of Fair Value using Trinomial Tree Model and Inputs (Detail) - 12 months ended Dec. 31, 2019 - Trinomial Tree Model [member]	yr $ / shares	yr ¥ / shares
The Company 1st share options [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date \| $ / shares	$ 58.80
Exercise price \| $ / shares	$ 56.40
USISH stock option plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date \| ¥ / shares		¥ 15.84
Exercise price \| ¥ / shares		¥ 13.34
Risk free interest rate	2.70%	2.70%
USISH core employees stock ownership plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share price at the grant date \| ¥ / shares		¥ 16.30
Exercise price \| ¥ / shares		¥ 13.34
Bottom of range [member] \| The Company 1st share options [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility	27.77%	27.77%
Expected lives	4.8	4.8
Risk free interest rate	0.73%	0.73%
Bottom of range [member] \| USISH stock option plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility	45.07%	45.07%
Expected lives	3.0	3.0
Risk free interest rate	2.80%	2.80%
Bottom of range [member] \| USISH core employees stock ownership plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility	44.48%	44.48%
Expected lives	2.5	2.5
Risk free interest rate	2.60%	2.60%
Top of range [member] \| The Company 1st share options [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility	28.86%	28.86%
Expected lives	7.0	7.0
Risk free interest rate	0.80%	0.80%
Top of range [member] \| USISH stock option plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility	51.80%	51.80%
Expected lives	5.0	5.0
Risk free interest rate	2.97%	2.97%
Top of range [member] \| USISH core employees stock ownership plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Expected volatility	47.77%	47.77%
Expected lives	4.5	4.5
Risk free interest rate	2.83%	2.83%

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2019-01-01
-Paragraph 47
-Subparagraph a
-Clause i
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-URIDate 2019-03-27

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The option life of share options granted.

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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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.

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The exercise price of share options granted.

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The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

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