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Investment Securities, HTM Credit Quality Indicators (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
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Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | $ 3,705,857 | $ 3,738,747
US Treasury Securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 994 | 1,000
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 | 1,649,045 | 1,659,722
Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 871,331 | 885,476
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 | 42,972 | 43,693
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 | 320,057 | 324,182
Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 770,177 | 772,456
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 | 51,281 | 52,219
Not Rated [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 7,273 | 4,221
Not Rated [Member] | US Treasury Securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Not Rated [Member] | 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 | 7,273 | 4,221
Not Rated [Member] | Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Not Rated [Member] | 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 | 0 | 0
Not Rated [Member] | 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 | 0 | 0
Not Rated [Member] | Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Not Rated [Member] | 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 | 0 | 0
Fitch, AAA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 2,818,388 | 2,846,177
Fitch, AAA Rating [Member] | US Treasury Securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 994 | 1,000
Fitch, AAA Rating [Member] | 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 | 761,576 | 767,151
Fitch, AAA Rating [Member] | Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 871,331 | 885,476
Fitch, AAA Rating [Member] | 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 | 42,972 | 43,693
Fitch, AAA Rating [Member] | 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 | 320,057 | 324,182
Fitch, AAA Rating [Member] | Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 770,177 | 772,456
Fitch, AAA Rating [Member] | 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 | 51,281 | 52,219
Fitch, AA Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 876,276 | 883,438
Fitch, AA Rating [Member] | US Treasury Securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Fitch, AA Rating [Member] | 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 | 876,276 | 883,438
Fitch, AA Rating [Member] | Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Fitch, AA Rating [Member] | 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 | 0 | 0
Fitch, AA Rating [Member] | 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 | 0 | 0
Fitch, AA Rating [Member] | Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Fitch, AA Rating [Member] | 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 | 0 | 0
Fitch, A Rating [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 3,920 | 4,911
Fitch, A Rating [Member] | US Treasury Securities |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Fitch, A Rating [Member] | 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 | 3,920 | 4,911
Fitch, A Rating [Member] | Residential Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Fitch, A Rating [Member] | 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 | 0 | 0
Fitch, A Rating [Member] | 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 | 0 | 0
Fitch, A Rating [Member] | Commercial Mortgage-Backed Securities [Member] | US Government Sponsored-Enterprise Insured Loans |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 | 0
Fitch, A Rating [Member] | 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 | $ 0 | $ 0

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