XML 68 R53.htm IDEA: XBRL DOCUMENT v3.20.4
Stock-Based Compensation - Summary of Fair Values of Performance Stock Units Granted and Assumptions used in Monte Carlo Simulation Pricing Model (Detail) - Performance Stock Units [Member]
12 Months Ended
Dec. 31, 2020
$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Estimated fair values of performance stock units granted $ 7.06
Risk-free interest rate 1.71%
Expected volatility 75.00%
Expected term (in years) 3 years