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Investment Securities, HTM Credit Quality Indicators (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | $ 3,738,747 | $ 3,860,235
Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 4,221 | 1,155
Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 2,846,177 | 2,938,090
Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 883,438 | 915,303
Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 4,911 | 5,687
US Treasury Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 1,000 | 999
US Treasury Securities [Member] | Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
US Treasury Securities [Member] | Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 1,000 | 999
US Treasury Securities [Member] | Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
US Treasury Securities [Member] | Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
US States and Political Subdivisions Debt Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 1,659,722 | 1,682,473
US States and Political Subdivisions Debt Securities [Member] | Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 4,221 | 1,155
US States and Political Subdivisions Debt Securities [Member] | Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 767,151 | 760,329
US States and Political Subdivisions Debt Securities [Member] | Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 883,438 | 915,303
US States and Political Subdivisions Debt Securities [Member] | Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 4,911 | 5,687
Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 885,476 | 941,973
Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 885,476 | 941,973
Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Residential Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 43,693 | 48,979
Residential Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Residential Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 43,693 | 48,979
Residential Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Residential Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Mortgage-Backed Securities, Issued by Private Enterprises [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 324,182 | 345,083
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 324,182 | 345,083
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Mortgage-Backed Securities, Issued by Private Enterprises [Member] | Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 772,456 | 780,995
Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 772,456 | 780,995
Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans [Member] | Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Commercial Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 52,219 | 59,733
Commercial Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Commercial Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 52,219 | 59,733
Commercial Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Commercial Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] | Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | $ 0 | $ 0

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