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Investment Securities - Summary of Amortized Cost of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
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Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | $ 7,969,672 | $ 8,444,362
Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 16,791 | 19,847
Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 2,767,869 | 3,109,411
Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,295,308 | 4,357,505
Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 824,734 | 891,909
CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 64,970 | 65,690
Aaa |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 363,636 | 406,877
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 | 298,666 | 341,187
Aaa | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 64,970 | 65,690
Aa1 |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 7,233,155 | 7,645,090
Aa1 | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 16,791 | 19,847
Aa1 | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 2,767,869 | 3,109,411
Aa1 | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,295,308 | 4,357,505
Aa1 | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 153,187 | 158,327
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 | 234,269 | 230,986
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 | 234,269 | 230,986
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 | 112,482 | 128,692
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 | 112,482 | 128,692
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 | 9,539 | 13,761
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 | 9,539 | 13,761
A1 | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Moody's, A2 Rating [Member] |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,165 | 0
Moody's, A2 Rating [Member] | Agency CMO |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Moody's, A2 Rating [Member] | Agency MBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Moody's, A2 Rating [Member] | Agency CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 0 | 0
Moody's, A2 Rating [Member] | Municipal bonds and notes |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | 4,165 | 0
Moody's, A2 Rating [Member] | 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 | 0 | 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 | 0 | 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 | 12,426 | 14,791
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 | 12,426 | 14,791
Not Rated | CMBS |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity | $ 0 | $ 0

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