Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Narrative (Details)

v3.19.3.a.u2
Stockholders' Equity - Narrative (Details) - USD ($)
 3 Months Ended
Oct. 11, 2019
Oct. 25, 2018
Oct. 03, 2018
Sep. 07, 2018
Sep. 05, 2018
Dec. 31, 2016
Dec. 31, 2019
Dec. 31, 2018
Oct. 10, 2019
Sep. 30, 2019
Feb. 27, 2015
Class of Stock [Line Items]                      
Stock compensation expense             $ 193,000 $ 238,000      
Number of shares authorized to be repurchased (up to)                 7,000    
Shares issued (in dollars per share)     $ 34.00                
Shares issued (in shares)     752,234                
Cost of shares     $ 25,575,956                
Restricted Stock                      
Class of Stock [Line Items]                      
Stock compensation expense             26,000 26,000      
Unrecognized expense             $ 43,000     $ 69,000  
Unrecognized compensation cost, expected recognition period             6 months        
Options                      
Class of Stock [Line Items]                      
Stock compensation expense             $ 82,000 $ 289,000      
Unrecognized expense             $ 797,000     $ 502,000  
Unrecognized compensation cost, expected recognition period             1 year 10 months 20 days        
2020 Option Grants                      
Class of Stock [Line Items]                      
Granted (in shares) 118,000                    
Shares issued (in dollars per share) $ 33.96                    
Period following an executive's termination of employment for a number of reasons 18 months                    
Period following an executive's termination of employment without cause 12 months                    
Share price (in dollars per share)             $ 35.83        
2020 Option Grants | Tranche One                      
Class of Stock [Line Items]                      
Period of consecutive trading days 20 days                    
Amount per share (in dollars per share) $ 35.00                    
Percentage of options 25.00%                    
2020 Option Grants | Tranche Two                      
Class of Stock [Line Items]                      
Period of consecutive trading days 20 days                    
Amount per share (in dollars per share) $ 40.00                    
Percentage of options 25.00%                    
2020 Option Grants | Tranche Three                      
Class of Stock [Line Items]                      
Period of consecutive trading days 20 days                    
Amount per share (in dollars per share) $ 45.00                    
Percentage of options 25.00%                    
2020 Option Grants | Tranche Four                      
Class of Stock [Line Items]                      
Period of consecutive trading days 20 days                    
Amount per share (in dollars per share) $ 50.00                    
Percentage of options 25.00%                    
2020 Option Grants | Options                      
Class of Stock [Line Items]                      
Grants in period, weighted average (in dollars per share)             3.20        
2020 Option Grants | Maximum                      
Class of Stock [Line Items]                      
Share price (in dollars per share)             $ 35.00        
2019 Option Grants                      
Class of Stock [Line Items]                      
Shares issued (in dollars per share)   $ 33.34                  
Number of awards vesting (in shares)             0        
Period following an executive's termination of employment for a number of reasons   18 months                  
Period following an executive's termination of employment without cause   12 months                  
Share price (in dollars per share)             $ 35.83        
2019 Option Grants | Tranche One                      
Class of Stock [Line Items]                      
Number of awards vesting (in shares)   3,333                  
Period of consecutive trading days   20 days                  
Amount per share (in dollars per share)   $ 40.00                  
2019 Option Grants | Tranche Two                      
Class of Stock [Line Items]                      
Number of awards vesting (in shares)   3,333                  
Period of consecutive trading days   20 days                  
Amount per share (in dollars per share)   $ 45.00                  
2019 Option Grants | Tranche Three                      
Class of Stock [Line Items]                      
Number of awards vesting (in shares)   3,334                  
Period of consecutive trading days   20 days                  
Amount per share (in dollars per share)   $ 50.00                  
2019 Option Grants | Options                      
Class of Stock [Line Items]                      
Grants in period, weighted average (in dollars per share)             7.10        
2019 Option Grants | Maximum                      
Class of Stock [Line Items]                      
Share price (in dollars per share)             $ 40.00        
2018 Option Grants                      
Class of Stock [Line Items]                      
Stock compensation expense             $ (823,000)        
Shares issued (in dollars per share)       $ 33.60              
Number of awards vesting (in shares)             0        
Period following an executive's termination of employment for a number of reasons       18 months              
Period following an executive's termination of employment without cause       12 months              
Share price (in dollars per share)             $ 35.83        
2018 Option Grants | Tranche One                      
Class of Stock [Line Items]                      
Period of consecutive trading days       20 years              
Amount per share (in dollars per share)       $ 35.00              
Percentage of options       25.00%              
2018 Option Grants | Tranche Two                      
Class of Stock [Line Items]                      
Period of consecutive trading days       20 years              
Amount per share (in dollars per share)       $ 40.00              
Percentage of options       25.00%              
2018 Option Grants | Tranche Three                      
Class of Stock [Line Items]                      
Period of consecutive trading days       20 years              
Amount per share (in dollars per share)       $ 45.00              
Percentage of options       25.00%              
2018 Option Grants | Tranche Four                      
Class of Stock [Line Items]                      
Period of consecutive trading days       20 years              
Amount per share (in dollars per share)       $ 50.00              
Percentage of options       25.00%              
2018 Option Grants | Maximum                      
Class of Stock [Line Items]                      
Share price (in dollars per share)             $ 35.00        
2016 Option Grants                      
Class of Stock [Line Items]                      
Shares issued (in dollars per share)           $ 27.15          
Number of awards vesting (in shares)             0        
Period of consecutive trading days           20 days          
Period following an executive's termination of employment for a number of reasons           18 months          
Share price (in dollars per share)             $ 35.83        
2016 Option Grants | Tranche One                      
Class of Stock [Line Items]                      
Amount per share (in dollars per share)           $ 60.00          
Percentage of options           25.00%          
2016 Option Grants | Tranche Two                      
Class of Stock [Line Items]                      
Amount per share (in dollars per share)           $ 75.00          
Percentage of options           25.00%          
2016 Option Grants | Tranche Three                      
Class of Stock [Line Items]                      
Amount per share (in dollars per share)           $ 90.00          
Percentage of options           25.00%          
2016 Option Grants | Tranche Four                      
Class of Stock [Line Items]                      
Amount per share (in dollars per share)           $ 105.00          
Percentage of options           25.00%          
2016 Option Grants | Maximum                      
Class of Stock [Line Items]                      
Share price (in dollars per share)             60.00        
2019 Modified Option Grants | Options                      
Class of Stock [Line Items]                      
Grants in period, weighted average (in dollars per share)             $ 1.40        
2015 Option Grants                      
Class of Stock [Line Items]                      
Number of shares authorized to be repurchased (up to)                     1,250,000
2015 Option Grants | Minimum                      
Class of Stock [Line Items]                      
Award vesting period             1 year        
Chief Executive Officer | 2018 Option Grants                      
Class of Stock [Line Items]                      
Granted (in shares)       210,000              
Award expiration period             6 months        
Chief Executive Officer | 2018 Option Grants | Tranche One                      
Class of Stock [Line Items]                      
Period of consecutive trading days             20 days        
Amount per share (in dollars per share)             $ 35.00        
Number of shares expected to vest (in shares)             26,250        
Chief Executive Officer | 2018 Option Grants | Tranche Two                      
Class of Stock [Line Items]                      
Period of consecutive trading days             20 days        
Amount per share (in dollars per share)             $ 40.00        
Number of shares expected to vest (in shares)             26,250        
Chief Executive Officer | 2016 Option Grants                      
Class of Stock [Line Items]                      
Granted (in shares)           300,000          
Board of Directors Chairman | 2016 Option Grants                      
Class of Stock [Line Items]                      
Granted (in shares)           225,000          
Shares forfeited (in shares)         187,500            
Chief Financial Officer | 2019 Option Grants                      
Class of Stock [Line Items]                      
Granted (in shares)   10,000                  
Chief Financial Officer | 2018 Option Grants                      
Class of Stock [Line Items]                      
Granted (in shares)       90,000