Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Narrative (Details)

v3.10.0.1
Stockholders' Equity - Narrative (Details)
 1 Months Ended 3 Months Ended 12 Months Ended
Oct. 25, 2018
$ / shares
shares
Oct. 03, 2018
USD ($)
$ / shares
shares
Sep. 07, 2018
$ / shares
shares
Apr. 27, 2018
USD ($)
Apr. 16, 2018
USD ($)
Dec. 31, 2016
$ / shares
shares
Nov. 30, 2017
$ / shares
shares
Dec. 31, 2018
USD ($)
$ / shares
shares
Dec. 31, 2017
USD ($)
Sep. 30, 2018
USD ($)
$ / shares
Sep. 30, 2016
$ / shares
Sep. 30, 2015
executive
$ / shares
shares
Sep. 30, 2017
USD ($)
shares
May 31, 2017
shares
Mar. 31, 2017
shares
Class of Stock [Line Items]                              
Shares issued (in dollars per share)   $ 34.00                          
Shares of common stock authorized to be repurchased (up to) (in shares) | shares                         7,000,000 2,000,000 5,000,000
Shares issued (in shares) | shares   752,234                          
Cost of shares | $   $ 25,575,956                          
Cash capital contribution required, due to catastrophe | $         $ 2,041,000                    
Capital contribution received from parent | $       $ 1,041,000                      
Capital contribution received from noncontrolling interest | $               $ 1,000,000              
Corporate, General and Administrative Expense                              
Class of Stock [Line Items]                              
Stock-based compensation expense | $               238,000 $ 192,000            
Restricted Stock                              
Class of Stock [Line Items]                              
Stock-based compensation expense | $               26,000 26,000            
Restricted shares awarded (in shares) | shares             5,000         12,500      
Number of senior executives | executive                       2      
Weighted average fair value (in dollars per share)             $ 31.95         $ 49.49      
Award vesting period             3 years                
Unrecognized expense | $               146,000         $ 172,000    
Employee Stock Option                              
Class of Stock [Line Items]                              
Stock-based compensation expense | $               289,000 $ 205,000            
Unrecognized expense | $               $ 2,553,000   $ 2,842,000          
Weighted average remaining contractual term               1 year 11 months 23 days              
2017 Authorization Program                              
Class of Stock [Line Items]                              
Authorized amount | $               $ 1,676,443              
Minimum | Restricted Stock                              
Class of Stock [Line Items]                              
Award vesting period                       3 years      
Maximum | Restricted Stock                              
Class of Stock [Line Items]                              
Award vesting period                       5 years      
2019 Option Grants                              
Class of Stock [Line Items]                              
Shares issued (in dollars per share) $ 33.34                            
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) $ 29.50                            
2019 Option Grants | Mr. Kiernan                              
Class of Stock [Line Items]                              
Options granted in period (in shares) | shares 10,000                            
2019 Option Grants | Tranche One                              
Class of Stock [Line Items]                              
Number of awards vesting (in shares) | shares 3,333                            
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) | shares 3,333                            
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) | shares 3,334                            
Amount per share (in dollars per share) $ 50.00                            
2019 Option Grants | Employee Stock Option                              
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]                              
Shares issued (in dollars per share)     $ 33.60                        
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)               29.50              
2018 Option Grants | Remy W. Trafelet                              
Class of Stock [Line Items]                              
Options granted in period (in shares) | shares     210,000                        
2018 Option Grants | Mr. Kiernan                              
Class of Stock [Line Items]                              
Options granted in period (in shares) | shares     90,000                        
2018 Option Grants | Tranche One                              
Class of Stock [Line Items]                              
Amount per share (in dollars per share)     $ 35.00                        
Percentage of options     25.00%                        
Period of consecutive trading days     20 years                        
2018 Option Grants | Tranche One | Henry R. Slack                              
Class of Stock [Line Items]                              
Amount per share (in dollars per share)               $ 35.00              
Period of consecutive trading days               20 days              
Number of shares expected to vest (in shares) | shares               26,250              
2018 Option Grants | Tranche Two                              
Class of Stock [Line Items]                              
Amount per share (in dollars per share)     $ 40.00                        
Percentage of options     25.00%                        
Period of consecutive trading days     20 years                        
2018 Option Grants | Tranche Two | Henry R. Slack                              
Class of Stock [Line Items]                              
Amount per share (in dollars per share)               $ 40.00              
Period of consecutive trading days               20 days              
Number of shares expected to vest (in shares) | shares               26,250              
2018 Option Grants | Tranche Three                              
Class of Stock [Line Items]                              
Amount per share (in dollars per share)     $ 45.00                        
Percentage of options     25.00%                        
Period of consecutive trading days     20 years                        
2018 Option Grants | Tranche Four                              
Class of Stock [Line Items]                              
Amount per share (in dollars per share)     $ 50.00                        
Percentage of options     25.00%                        
Period of consecutive trading days     20 years                        
2018 Option Grants | Employee Stock Option                              
Class of Stock [Line Items]                              
Grants in period, weighted average (in dollars per share)                   $ 7.40          
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                  
Period following an executive's termination of employment for a number of reasons           18 months                  
Period of consecutive trading days           20 days                  
2016 Option Grants | Remy W. Trafelet                              
Class of Stock [Line Items]                              
Options granted in period (in shares) | shares           300,000                  
2016 Option Grants | Henry R. Slack                              
Class of Stock [Line Items]                              
Unrecognized expense | $                   $ 783,000          
Options granted in period (in shares) | shares           225,000                  
Shares forfeited (in shares) | shares           187,500                  
2016 Option Grants | George R. Brokaw                              
Class of Stock [Line Items]                              
Options granted in period (in shares) | shares           225,000                  
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 | Employee Stock Option                              
Class of Stock [Line Items]                              
Grants in period, weighted average (in dollars per share)                     $ 3.53        
2015 Option Grants | Employee Stock Option                              
Class of Stock [Line Items]                              
Common shares available (in shares) | shares               557,500