v3.26.1
Fair Value Measurements (Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets $ 45,403 $ 46,120
Derivative liabilities 27,078 36,259
Total recurring fair value measurements - liabilities 1,000 1,300
Recurring [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 6,006,220 5,961,917
Mortgage loans held for sale 42,867 33,158
Derivative assets [1] 49,137 63,126
Total fair value measurements 6,098,224 6,058,201
Derivative liabilities [1] 91,681 95,367
Total recurring fair value measurements - liabilities 91,681 95,367
Recurring [Member] | U.S. Treasury And Government Agency Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 289,507 269,332
Recurring [Member] | Municipal Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 163,857 191,328
Recurring [Member] | Residential Mortgage-Backed Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 2,262,861 2,375,629
Recurring [Member] | Commercial Mortgage-Backed Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 3,248,699 3,083,325
Recurring [Member] | Collateralized Mortgage Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 21,796 25,946
Recurring [Member] | Corporate Debt Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 19,500 16,357
Recurring [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 6,006,220 5,961,917
Mortgage loans held for sale 42,867 33,158
Derivative assets [1] 49,137 63,126
Total fair value measurements 6,098,224 6,058,201
Derivative liabilities [1] 90,695 94,083
Total recurring fair value measurements - liabilities 90,695 94,083
Recurring [Member] | Level 2 [Member] | U.S. Treasury And Government Agency Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 289,507 269,332
Recurring [Member] | Level 2 [Member] | Municipal Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 163,857 191,328
Recurring [Member] | Level 2 [Member] | Residential Mortgage-Backed Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 2,262,861 2,375,629
Recurring [Member] | Level 2 [Member] | Commercial Mortgage-Backed Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 3,248,699 3,083,325
Recurring [Member] | Level 2 [Member] | Collateralized Mortgage Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 21,796 25,946
Recurring [Member] | Level 2 [Member] | Corporate Debt Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 19,500 16,357
Recurring [Member] | Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative liabilities [1] 986 1,284
Total recurring fair value measurements - liabilities $ 986 $ 1,284
[1] For further disaggregation of derivative assets and liabilities, see Note 6 - Derivatives.