Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Shares Used in Computation of Basic and Diluted Per Share Information (Detail)

v3.20.4
Summary of Significant Accounting Policies - Shares Used in Computation of Basic and Diluted Per Share Information (Detail) - shares
3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Weighted average shares outstanding:                      
Weighted average number of shares outstanding for basic per share calculation (in shares) 31,128,485 31,120,648 31,104,377 31,020,224 30,977,812 30,970,589 30,960,468 30,837,290 31,092,417 30,932,607 27,498,351
Effect of dilutive potential shares:                      
Nonvested restricted stock (in shares)                 273,348 277,217 275,045
Adjusted weighted average shares for diluted per share calculation (in shares) 31,442,674 31,410,862 31,324,474 31,303,172 31,270,149 31,247,196 31,200,930 31,187,098 31,365,765 31,209,824 27,773,396
Antidilutive shares (in shares)                 1,155 157,608 46,002