Annual report pursuant to Section 13 and 15(d)

Stock Based Compensation - Performance Share Units - Additional Information (Detail)

v3.21.1
Stock Based Compensation - Performance Share Units - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Performance Share Units [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Allocated share-based compensation expense $ (88,348) $ 88,348
Performance Shares [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period 267,677  
Allocated share-based compensation expense $ (88,348) $ 88,348
Share based compensation arrangement by share based payment award unamortized value $ 0  
2015 Performance Share Unit Plan [Member] | Employee [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period 267,677