Schedule II - Condensed Financial Information of Registrant (Parent Company Only) (Balance Sheet) (Details) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
ASSETS        
Cash and cash equivalents $ 114,446 $ 130,985 $ 141,666 $ 85,145
Investment in subsidiaries 1,702 1,702    
Deferred federal income taxes 1,779      
Other assets 11,245 7,879    
Total assets 1,076,600 980,869    
LIABILITIES AND STOCKHOLDERS' EQUITY        
Revolving credit facility payable 30,000      
Subordinated debt securities 56,702 56,702    
Accrued Income Taxes   968    
Accounts payable and other accrued expenses 23,253 25,766    
Total liabilities 814,574 728,832    
Stockholders' equity:        
Common stock, $.18 par value, authorized 33,333,333 shares; issued 20,872,831 shares in 2013 and in 2012 3,757 3,757    
Capital in excess of par value 123,480 123,194    
Retained earnings 141,501 119,638    
Accumulated other comprehensive income 7,418 17,801    
Treasury stock (1,775,512 shares in 2015 and 1,655,306 in 2014), at cost (14,130) (12,353)    
Total stockholders equity 262,026 252,037 238,118 220,537
Total liabilities and stockholders' equity 1,076,600 980,869    
Parent Company [Member]        
ASSETS        
Cash and cash equivalents 8,014 11,839 $ 8,063 $ 1,112
Investment in subsidiaries 361,769 325,608    
Deferred federal income taxes 942 747    
Other assets 4,488 4,061    
Total assets 375,213 342,255    
LIABILITIES AND STOCKHOLDERS' EQUITY        
Revolving credit facility payable 30,000      
Subordinated debt securities 56,702 56,702    
Current federal income tax payable 72 64    
Accounts payable and other accrued expenses 26,413 33,452    
Total liabilities 113,187 90,218    
Stockholders' equity:        
Common stock, $.18 par value, authorized 33,333,333 shares; issued 20,872,831 shares in 2013 and in 2012 3,757 3,757    
Capital in excess of par value 123,480 123,194    
Retained earnings 141,501 119,638    
Accumulated other comprehensive income 7,418 17,801    
Treasury stock (1,775,512 shares in 2015 and 1,655,306 in 2014), at cost (14,130) (12,353)    
Total stockholders equity 262,026 252,037    
Total liabilities and stockholders' equity $ 375,213 $ 342,255