v3.26.1
Note 9 - Fair Value Measurements - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Debt securities available for sale $ 3,596,855 $ 3,468,734
Equity securities held for trading at fair value 219 466
Total investment securities 14,446 14,693
Agency Residential MBS [Member]    
Debt securities available for sale 177,308 184,346
Agency Commercial MBS [Member]    
Debt securities available for sale 946,114 707,560
US Government Agencies Debt Securities [Member]    
Debt securities available for sale 298,502 302,412
US States and Political Subdivisions Debt Securities [Member]    
Debt securities available for sale 45,422 45,722
Corporate Debt Securities [Member]    
Debt securities available for sale 1,835,522 1,804,080
Fair Value, Recurring [Member]    
Debt securities available for sale 3,596,855 3,468,734
Equity securities held for trading at fair value 219 466
Total investment securities 3,597,074 3,469,200
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Debt securities available for sale 0 0
Equity securities held for trading at fair value 219 466
Total investment securities 219 466
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]    
Debt securities available for sale 3,596,855 3,468,734
Equity securities held for trading at fair value 0 0
Total investment securities 3,596,855 3,468,734
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Debt securities available for sale 0 [1] 0 [2]
Equity securities held for trading at fair value 0 [1] 0 [2]
Total investment securities 0 [1] 0 [2]
Fair Value, Recurring [Member] | Agency Residential MBS [Member]    
Debt securities available for sale 177,308 184,346
Fair Value, Recurring [Member] | Agency Residential MBS [Member] | Fair Value, Inputs, Level 1 [Member]    
Debt securities available for sale 0 0
Fair Value, Recurring [Member] | Agency Residential MBS [Member] | Fair Value, Inputs, Level 2 [Member]    
Debt securities available for sale 177,308 184,346
Fair Value, Recurring [Member] | Agency Residential MBS [Member] | Fair Value, Inputs, Level 3 [Member]    
Debt securities available for sale 0 [1] 0 [2]
Fair Value, Recurring [Member] | Agency Commercial MBS [Member]    
Debt securities available for sale 946,114 707,560
Fair Value, Recurring [Member] | Agency Commercial MBS [Member] | Fair Value, Inputs, Level 1 [Member]    
Debt securities available for sale 0 0
Fair Value, Recurring [Member] | Agency Commercial MBS [Member] | Fair Value, Inputs, Level 2 [Member]    
Debt securities available for sale 946,114 707,560
Fair Value, Recurring [Member] | Agency Commercial MBS [Member] | Fair Value, Inputs, Level 3 [Member]    
Debt securities available for sale 0 [1] 0 [2]
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member]    
Debt securities available for sale 298,502 302,412
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]    
Debt securities available for sale 0 0
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]    
Debt securities available for sale 298,502 302,412
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]    
Debt securities available for sale 0 [1] 0 [2]
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member]    
Debt securities available for sale 45,422 45,722
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]    
Debt securities available for sale 0 0
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]    
Debt securities available for sale 45,422 45,722
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]    
Debt securities available for sale 0 [1] 0 [2]
Fair Value, Recurring [Member] | Corporate Debt Securities [Member]    
Debt securities available for sale 1,835,522 1,804,080
Fair Value, Recurring [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]    
Debt securities available for sale 0 0
Fair Value, Recurring [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]    
Debt securities available for sale 1,835,522 1,804,080
Fair Value, Recurring [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]    
Debt securities available for sale 0 [1] 0 [2]
Fair Value, Recurring [Member] | Collateralized Loan Obligations [Member]    
Debt securities available for sale 293,987 424,614
Fair Value, Recurring [Member] | Collateralized Loan Obligations [Member] | Fair Value, Inputs, Level 1 [Member]    
Debt securities available for sale 0 0
Fair Value, Recurring [Member] | Collateralized Loan Obligations [Member] | Fair Value, Inputs, Level 2 [Member]    
Debt securities available for sale 293,987 424,614
Fair Value, Recurring [Member] | Collateralized Loan Obligations [Member] | Fair Value, Inputs, Level 3 [Member]    
Debt securities available for sale $ 0 [1] $ 0 [2]
[1] There were no transfers into or out of level 3 during the three months ended March 31, 2026.
[2] There were no transfers into or out of level 3 during the year ended December 31, 2025.