v3.26.1
Investments (Aggregate Carrying And Approximate Market Values Of Available-For-Sale Securities) (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]    
Total $ 1,583,311 $ 1,602,721
Gross Unrealized Gains 3,503 8,546
Gross Unrealized Losses 110,089 107,909
Estimated Fair Value 1,476,725 1,503,358
Obligations of states and political subdivisions    
Debt Securities, Available-for-sale [Line Items]    
Total 185,915 189,276
Gross Unrealized Gains 905 538
Gross Unrealized Losses 9,486 10,090
Estimated Fair Value 177,334 179,724
U.S. government agencies    
Debt Securities, Available-for-sale [Line Items]    
Total 1,371,095 1,387,057
Gross Unrealized Gains 2,395 7,836
Gross Unrealized Losses 99,894 97,104
Estimated Fair Value 1,273,596 1,297,789
Private label    
Debt Securities, Available-for-sale [Line Items]    
Total 5,055 5,068
Gross Unrealized Gains 0 0
Gross Unrealized Losses 72 36
Estimated Fair Value 4,983 5,032
Trust preferred securities    
Debt Securities, Available-for-sale [Line Items]    
Total 4,616 4,612
Gross Unrealized Gains 0 0
Gross Unrealized Losses 78 188
Estimated Fair Value 4,538 4,424
Corporate securities    
Debt Securities, Available-for-sale [Line Items]    
Total 16,630 16,708
Gross Unrealized Gains 203 172
Gross Unrealized Losses 559 491
Estimated Fair Value $ 16,274 $ 16,389