v3.26.1
Investment Securities - Schedule of Securities Held-to-Maturity (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Schedule of Held-to-maturity Securities [Line Items]    
Amortization cost   $ 2,309,331
Allowance for Credit Loss $ 0 (695)
Net carrying amount 0 2,308,636
Gross unrealized gains   2,052
Gross unrealized losses   (64,162)
Securities held to maturity, fair value 0 2,246,526
Interest receivable 19,400 11,400
Estimate of Fair Value Measurement | Recurring | Investment in FRB and FHLB stock    
Schedule of Held-to-maturity Securities [Line Items]    
Assets 181,352 160,442
Level 1 | Estimate of Fair Value Measurement | Recurring | Investment in FRB and FHLB stock    
Schedule of Held-to-maturity Securities [Line Items]    
Assets $ 0 0
Securities HTM    
Schedule of Held-to-maturity Securities [Line Items]    
Interest receivable   13,400
Municipal securities    
Schedule of Held-to-maturity Securities [Line Items]    
Amortization cost   1,237,792
Allowance for Credit Loss   (20)
Net carrying amount   1,237,772
Gross unrealized gains   2,052
Gross unrealized losses   (20,713)
Securities held to maturity, fair value   1,219,111
Agency commercial MBS    
Schedule of Held-to-maturity Securities [Line Items]    
Amortization cost   447,283
Allowance for Credit Loss   0
Net carrying amount   447,283
Gross unrealized gains   0
Gross unrealized losses   (19,645)
Securities held to maturity, fair value   427,638
Private label commercial MBS    
Schedule of Held-to-maturity Securities [Line Items]    
Amortization cost   360,382
Allowance for Credit Loss   0
Net carrying amount   360,382
Gross unrealized gains   0
Gross unrealized losses   (9,606)
Securities held to maturity, fair value   350,776
U.S. Treasury securities    
Schedule of Held-to-maturity Securities [Line Items]    
Amortization cost   193,022
Allowance for Credit Loss   0
Net carrying amount   193,022
Gross unrealized gains   0
Gross unrealized losses   (7,934)
Securities held to maturity, fair value   185,088
Corporate debt securities    
Schedule of Held-to-maturity Securities [Line Items]    
Amortization cost   70,852
Allowance for Credit Loss   (675)
Net carrying amount   70,177
Gross unrealized gains   0
Gross unrealized losses   (6,264)
Securities held to maturity, fair value   $ 63,913