XML 108 R96.htm IDEA: XBRL DOCUMENT v3.25.2
Financial Instruments - Amortized Cost and Fair Value of Securities Available-for-Sale (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value $ 2,899,968 $ 3,072,639
U.S. government-sponsored enterprises    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 264,964 284,790
U.S. government-sponsored mortgage-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 1,239,329 1,324,684
Private mortgage-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 155,582 171,394
Non-government-sponsored asset backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 183,543 225,648
State and political subdivisions    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 845,261 870,361
Other securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 211,289 195,762
Fair Value, Recurring    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 2,899,968 3,072,639
Fair Value, Recurring | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 2,879,784 3,051,110
Fair Value, Recurring | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 20,184 21,529
Fair Value, Recurring | U.S. government-sponsored enterprises    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 264,964 284,790
Fair Value, Recurring | U.S. government-sponsored enterprises | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | U.S. government-sponsored enterprises | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 264,964 284,790
Fair Value, Recurring | U.S. government-sponsored enterprises | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | U.S. government-sponsored mortgage-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 1,239,329 1,324,684
Fair Value, Recurring | U.S. government-sponsored mortgage-backed securities | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | U.S. government-sponsored mortgage-backed securities | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 1,239,329 1,324,684
Fair Value, Recurring | U.S. government-sponsored mortgage-backed securities | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | Private mortgage-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 155,582 171,394
Fair Value, Recurring | Private mortgage-backed securities | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | Private mortgage-backed securities | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 155,582 171,394
Fair Value, Recurring | Private mortgage-backed securities | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | Non-government-sponsored asset backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 183,543 225,648
Fair Value, Recurring | Non-government-sponsored asset backed securities | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | Non-government-sponsored asset backed securities | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 183,543 225,648
Fair Value, Recurring | Non-government-sponsored asset backed securities | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | State and political subdivisions    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 845,261 870,361
Fair Value, Recurring | State and political subdivisions | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | State and political subdivisions | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 829,947 853,699
Fair Value, Recurring | State and political subdivisions | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 15,314 16,662
Fair Value, Recurring | Other securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 211,289 195,762
Fair Value, Recurring | Other securities | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 0 0
Fair Value, Recurring | Other securities | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value 206,419 190,895
Fair Value, Recurring | Other securities | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated Fair Value $ 4,870 $ 4,867