Financial Risk Management and Financial Instruments - Summary of Assumption Used to Estimate Fair Value of Warrants (Details) - Warrants |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2019
USD ($)
yr
|
Dec. 31, 2018
USD ($)
yr
|
Dec. 31, 2017
USD ($)
yr
|
|
| Disclosure Of Significant Unobservable Inputs Used In Fair Value Measurement Of Liabilities [Line Items] | |||
| Share price (US$) | $ | $ 149.55 | $ 113.50 | $ 120.50 |
| Historical Volatility for Shares, Measurement Input | |||
| Disclosure Of Significant Unobservable Inputs Used In Fair Value Measurement Of Liabilities [Line Items] | |||
| Volatility (%) | 32.5 | 40.0 | 30.0 |
| Bottom of Range | |||
| Disclosure Of Significant Unobservable Inputs Used In Fair Value Measurement Of Liabilities [Line Items] | |||
| Expected term (years) | 0.5 | 0.8 | 0.9 |
| Risk free rate (%) | 1.58% | 2.55% | 1.71% |
| Top of Range | |||
| Disclosure Of Significant Unobservable Inputs Used In Fair Value Measurement Of Liabilities [Line Items] | |||
| Expected term (years) | 2.5 | 1.5 | 1.1 |
| Risk free rate (%) | 1.59% | 2.58% | 1.76% |