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Investment Securities - Summary of Amortized Cost of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | $ 8,444,362 | $ 7,074,797
Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 19,847 | 23,470
Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 3,109,411 | 2,409,521
Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,357,505 | 3,625,627
Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 891,909 | 916,104
CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 65,690 | 100,075
Aaa |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 406,877 | 433,554
Aaa | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aaa | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aaa | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aaa | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 341,187 | 333,479
Aaa | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 65,690 | 100,075
Aa1 |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 7,645,090 | 6,221,233
Aa1 | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 19,847 | 23,470
Aa1 | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 3,109,411 | 2,409,521
Aa1 | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,357,505 | 3,625,627
Aa1 | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 158,327 | 162,615
Aa1 | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa2 |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 230,986 | 253,671
Aa2 | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa2 | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa2 | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa2 | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 230,986 | 253,671
Aa2 | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa3 |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 128,692 | 115,404
Aa3 | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa3 | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa3 | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Aa3 | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 128,692 | 115,404
Aa3 | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A1 |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 13,761 | 32,732
A1 | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A1 | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A1 | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A1 | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 13,761 | 32,732
A1 | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A3 |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,165 | 4,165
A3 | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A3 | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A3 | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
A3 | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,165 | 4,165
A3 | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Not Rated |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 14,791 | 14,038
Not Rated | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Not Rated | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Not Rated | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Not Rated | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 14,791 | 14,038
Not Rated | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | $ 0 | $ 0

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