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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
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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%

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The option life of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition 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]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + Details
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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 exercise price of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition 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]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2019-03-27 + Details
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