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Employee Deferred Compensation Plan and Employee Stock Purchase Plan - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 12 Months Ended
Jun. 30, 2001
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Mar. 08, 2022
Aug. 30, 2021
Nov. 05, 2018
Jun. 06, 2018
Employee Stock Ownership Plan E S O P Disclosures [Line Items]                
Percentage contribution, compensation   100.00%            
Matching percentage, employee contribution   5.00%            
Company's contributions amount   $ 2,273 $ 2,172 $ 1,997        
Common stock under employee stock purchase plan, par value   $ 10 $ 10   $ 0.10 $ 0.10 $ 0.10  
Shares of common stock purchased through the plan   50,782 49,668 47,229        
Employee Stock Purchase Plan                
Employee Stock Ownership Plan E S O P Disclosures [Line Items]                
Number of common stock shares under employee stock purchase plan 1,000,000              
Common stock under employee stock purchase plan, par value $ 0.10              
Employee stock purchase plan offering period   January 1 and July 1 of each year            
Employee stock purchase plan expiration date   Dec. 31, 2028            
Commons stock plan available for sale under plan               995,000
Available common stock under plan   543,180 593,962 643,630