XML 53 R42.htm IDEA: XBRL DOCUMENT v3.20.2
Earnings Per Share - Additional Information (Detail) - USD ($)
3 Months Ended 9 Months Ended
Mar. 31, 2020
Sep. 30, 2020
Dec. 31, 2019
Accelerated Share Repurchases [Line Items]      
Stock Repurchased and Retired During Period, Shares 313,998    
Stock Repurchased and Retired During Period, Value $ 20,900,000 $ 20,881,000  
Stock Purchase Initiated but not yet Settled, Shares 18,000    
Share Repurchases Initiated but not yet Settled     $ 1,200,000
Share Repurchase Program [Member]      
Accelerated Share Repurchases [Line Items]      
Share repurchase authorized amount   125,000,000  
Stock Repurchase Program, Remaining Authorized Repurchase Amount   $ 100,000