Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation - Additional Information (Detail)

v3.19.1
Stock Based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock option expense $ 0 $ 4,000
Amortization of non-vested stock grants and performance-based awards $ 1,396,000 $ 1,495,000
Stock options exercised by employees and directors 0 0
Number of shares of non-vested stock that vested 16,821 36,191
Employees [Member] | Non-Vested Shares [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock option plan, share based compensation, vesting period (in years) 5 years  
Shares of non-vested stock issued 1,000  
Fair market value of the non-vested stock on the date of grant $ 99.10  
Aggregate fair value $ 99,100  
Chief Executive Officer, David Rogers [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Compensation expense $ 400,000