Stockholders' Equity - Summary of Shares Issued and Held in Treasury or Outstanding (Detail) - shares |
Jun. 30, 2020 |
Dec. 31, 2019 |
---|---|---|
Class A Common Stock [Member] | ||
Class of Stock [Line Items] | ||
Common stock - issued | 17,205,821 | 17,136,493 |
Common stock - held in treasury | (1,987,520) | (1,692,059) |
Common stock - outstanding | 15,218,301 | 15,444,434 |
Class B Common Stock [Member] | ||
Class of Stock [Line Items] | ||
Common stock - issued | 234,903 | 234,903 |
Common stock - held in treasury | (234,903) | (234,903) |
Common stock - outstanding | 0 | 0 |