Share-based Compensation - Significant Inputs to Model to Determine Weighted Average Fair Value of Stock-options Granted (Detail) - Employee 2017 EIP [Member] - $ / shares |
12 Months Ended | |
|---|---|---|
Dec. 31, 2021 |
Dec. 31, 2020 |
|
| Disclosure of terms and conditions of share-based payment arrangement [Line Items] | ||
| Weighted average share price at grant date | $ 3.29 | $ 2.93 |
| Weighted average exercise price | $ 3.29 | $ 2.93 |
| Weighted average 10-year volatility | 76.00% | 77.00% |
| Dividend yield | 0.00% | 0.00% |
| Weighted average 10-year risk free rate | 1.45% | 1.28% |