Quarterly report pursuant to Section 13 or 15(d)

Earnings Per Share And Other Equity Related Information - Narrative (Details)

v3.19.2
Earnings Per Share And Other Equity Related Information - Narrative (Details) - USD ($)
 3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Aug. 31, 2019
Feb. 28, 2017
Apr. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock options excluded from calculation of dilutive shares as the effect would be anti-dilutive (in shares) 446,000 1,330,000 372,000 1,515,000      
Stock-based compensation expense $ 397,000 $ 392,000 $ 782,000 $ 747,000      
Open market purchase of treasury shares   $ 1,000   1,772,000      
Open market purchase of treasury shares, fees       $ 9,000      
Stock Options              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Non-vested stock options unrecognized compensation expense $ 4,311,000   $ 4,311,000        
Non-vested stock options unrecognized compensation expense, weighted-average period of recognition     3 years 1 month        
Common Class A              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock repurchase program, authorized amount (up to)           $ 15,000,000 $ 10,000,000
Treasury Stock              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Open market purchase of common shares (in shares) 0 100 0 212,231      
Open market purchase of treasury shares   $ 1,000   $ 1,772,000      
Subsequent Event | Common Class A              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock repurchase program, authorized amount (up to)         $ 17,553,000