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v3.25.1

Investment Securities, AFS and HTM Securities Amortized Costs and Fair Values (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Dec. 31, 2024
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | $ 4,789,259 | $ 4,605,954
Debt Securities, Available-for-Sale, Unrealized Gain | 23,197 | 5,693
Debt Securities, Available-for-Sale, Unrealized Loss | (15,885) | (30,213)
Debt Securities, Available-for-Sale | 4,796,570 | 4,581,434
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 3,705,857 | 3,738,747
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 40,432 | 42,653
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | (572,119) | (595,906)
Debt Securities, Held-to-Maturity, Fair Value | 3,174,170 | 3,185,494
US Treasury Securities |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 994 | 1,000
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 15 | 0
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | 0 | (1)
Debt Securities, Held-to-Maturity, Fair Value | 1,009 | 999
US States and Political Subdivisions Debt Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 3,063 | 3,063
Debt Securities, Available-for-Sale, Unrealized Gain | 0 | 0
Debt Securities, Available-for-Sale, Unrealized Loss | (68) | (58)
Debt Securities, Available-for-Sale | 2,995 | 3,005
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 1,649,045 | 1,659,722
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 662 | 1,122
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | (194,901) | (174,202)
Debt Securities, Held-to-Maturity, Fair Value | 1,454,805 | 1,486,642
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 0 |
Debt Securities, Available-for-Sale | 0 |
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 320,057 | 324,182
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 7,786 | 8,135
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | (59,642) | (65,963)
Debt Securities, Held-to-Maturity, Fair Value | 268,201 | 266,353
Federal Family Education Loan Program (FFELP) Guaranteed Loans [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 105,633 | 108,319
Debt Securities, Available-for-Sale, Unrealized Gain | 52 | 123
Debt Securities, Available-for-Sale, Unrealized Loss | (911) | (604)
Debt Securities, Available-for-Sale | 104,774 | 107,839
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 |
Debt Securities, Held-to-Maturity, Fair Value | 0 |
US Government-sponsored Enterprises Debt Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 427 | 495
Debt Securities, Available-for-Sale, Unrealized Gain | 0 | 0
Debt Securities, Available-for-Sale, Unrealized Loss | (17) | (24)
Debt Securities, Available-for-Sale | 410 | 471
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 0 |
Debt Securities, Held-to-Maturity, Fair Value | 0 |
Other Debt securities |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 3,000 | 3,000
Debt Securities, Available-for-Sale, Unrealized Gain | 0 | 0
Debt Securities, Available-for-Sale, Unrealized Loss | (1) | (11)
Debt Securities, Available-for-Sale | 2,999 | 2,989
US Government Sponsored-Enterprise Insured Loans | Residential Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 125,024 | 120,272
Debt Securities, Available-for-Sale, Unrealized Gain | 486 | 190
Debt Securities, Available-for-Sale, Unrealized Loss | (7,474) | (9,534)
Debt Securities, Available-for-Sale | 118,036 | 110,928
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 871,331 | 885,476
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 21,973 | 22,934
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | (169,482) | (186,464)
Debt Securities, Held-to-Maturity, Fair Value | 723,822 | 721,946
US Government Sponsored-Enterprise Insured Loans | Commercial Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 18,240 | 18,332
Debt Securities, Available-for-Sale, Unrealized Gain | 0 | 0
Debt Securities, Available-for-Sale, Unrealized Loss | (1,281) | (1,332)
Debt Securities, Available-for-Sale | 16,959 | 17,000
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 770,177 | 772,456
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 9,765 | 10,217
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | (139,208) | (159,078)
Debt Securities, Held-to-Maturity, Fair Value | 640,734 | 623,595
Government National Mortgage Association (GNMA) [Member] | Residential Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 4,418,218 | 4,236,199
Debt Securities, Available-for-Sale, Unrealized Gain | 22,659 | 5,379
Debt Securities, Available-for-Sale, Unrealized Loss | (1,913) | (13,851)
Debt Securities, Available-for-Sale | 4,438,964 | 4,227,727
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 42,972 | 43,693
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 14 | 9
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | (3,009) | (3,774)
Debt Securities, Held-to-Maturity, Fair Value | 39,977 | 39,927
Government National Mortgage Association (GNMA) [Member] | Commercial Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-Sale, Amortized Cost | 115,654 | 116,275
Debt Securities, Available-for-Sale, Unrealized Gain | 0 | 0
Debt Securities, Available-for-Sale, Unrealized Loss | (4,221) | (4,800)
Debt Securities, Available-for-Sale | 111,433 | 111,475
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss | 51,281 | 52,219
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain | 218 | 236
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss | (5,877) | (6,424)
Debt Securities, Held-to-Maturity, Fair Value | $ 45,621 | $ 46,032

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