Quarterly report pursuant to Section 13 or 15(d)

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

v3.19.3
Stock Based Compensation - Performance Share Units - Additional Information (Detail) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Performance Share Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated share-based compensation expense $ 0 $ 207,206 $ 0 $ 614,862