Quarterly report pursuant to Section 13 or 15(d)

Capital Transactions (Details)

v3.7.0.1
Capital Transactions (Details) - USD ($)
 3 Months Ended
Mar. 07, 2017
Mar. 31, 2017
Mar. 31, 2016
Dec. 31, 2016
Nov. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Cash dividend per common share (in dollars per share) $ 0.10 $ 0.10 $ 0.10    
Payments of cash dividends $ 1,900,000 $ 1,886,000 $ 1,872,000    
Weighted average exercise price per share   $ 12.41   $ 12.41  
Stock options          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Options to purchase   1,524,000   1,524,000  
Exercisable (in shares)   1,393,000   1,201,000  
Expected to vest (in shares)   124,000   306,000  
Aggregate Intrinsic value, outstanding   $ 800,000   $ 4,200,000  
Aggregate Intrinsic value, exercisable   800,000   3,700,000  
Aggregate Intrinsic value, expected to vest   0   400,000  
Exercised (in shares)     25,000    
Exercised (in dollars per share)     $ 2.35    
Aggregate intrinsic values of options exercised     $ 200,000    
Tax benefit from the exercise of stock options     100,000    
Time-based stock options          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Share-based compensation expense   100,000 $ 300,000    
Unrecognized share-based compensation expense   $ 200,000   $ 300,000  
Weighted-average period over which the remaining compensation cost is expected to be recognized   11 months      
Time-based stock options | Maximum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vesting period   48 months      
Performance based stock options operating income margins          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Operating income margin, one (as a percent)   6.00%      
Operating income margin, two (as a percent)   8.00%      
Operating income margin, three (as a percent)   10.00%      
2012 Stock Incentive Plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares authorized under the plan       1,500,000  
Additional number of shares authorized under the plan     1,500,000    
2009 Incentive Plan | Maximum          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares authorized under the plan   400,000      
2014 Share Repurchase Program          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Stock repurchase program, authorized amount         $ 20,000,000
Remaining balance available for repurchases   $ 13,400,000      
Repurchase of common stock (in shares)   0 0