XML 62 R48.htm IDEA: XBRL DOCUMENT v3.19.1
Shareholders Equity - Summary of Changes in Shareholders Equity (Parenthetical) (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Stockholders Equity Note [Line Items]    
Tax provision (benefit) for recognized net actuarial loss (gain) $ (32) $ (30)
Unrecognized Pension Benefit Cost [Member]    
Stockholders Equity Note [Line Items]    
Tax provision (benefit) for recognized net actuarial loss (gain) $ 32 $ 30
Treasury Stock [Member]    
Stockholders Equity Note [Line Items]    
Purchase of common shares 40,891 10,907
Common Shares [Member]    
Stockholders Equity Note [Line Items]    
Issuance of common shares 78,821 21,458
Paid In Capital [Member]    
Stockholders Equity Note [Line Items]    
Issuance of common shares 78,821 21,458
Common Shares Issued to Rabbi Trust [Member]    
Stockholders Equity Note [Line Items]    
Common shares issued to rabbi trust 705 112
Deferred Compensation Liability [Member]    
Stockholders Equity Note [Line Items]    
Common shares issued to rabbi trust 705 112
Retained Earnings [Member]    
Stockholders Equity Note [Line Items]    
Cash dividends declared per share $ 0.20 $ 0.20