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v3.25.4

Investment Securities - Summary of Debt Securities Held-to-Maturity (Detail) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Amortized Cost | $ 7,969,672 | $ 8,444,362 |  |
Gross Unrealized Gains | 25,062 | 1,502 |  |
Gross Unrealized Losses | (826,151) | (992,741) |  |
Fair Value | 7,168,583 | 7,453,123 |  |
Allowance for Credit Losses | (97) | (171) | $ (209) | $ (182)
Net Carrying Value | 7,969,575 | 8,444,191 |  |
Held-to-maturity Securities |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Interest receivable | 28,100 | 30,500 |  |
Agency CMO |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Amortized Cost | 16,791 | 19,847 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (1,071) | (1,671) |  |
Fair Value | 15,720 | 18,176 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Value | 16,791 | 19,847 |  |
Agency MBS |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Amortized Cost | 2,767,869 | 3,109,411 |  |
Gross Unrealized Gains | 24,073 | 771 |  |
Gross Unrealized Losses | (226,089) | (333,039) |  |
Fair Value | 2,565,853 | 2,777,143 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Value | 2,767,869 | 3,109,411 |  |
Agency CMBS |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Amortized Cost | 4,295,308 | 4,357,505 |  |
Gross Unrealized Gains | 0 | 414 |  |
Gross Unrealized Losses | (567,040) | (613,914) |  |
Fair Value | 3,728,268 | 3,744,005 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Value | 4,295,308 | 4,357,505 |  |
Municipal bonds and notes |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Amortized Cost | 824,734 | 891,909 |  |
Gross Unrealized Gains | 989 | 317 |  |
Gross Unrealized Losses | (30,461) | (40,266) |  |
Fair Value | 795,262 | 851,960 |  |
Allowance for Credit Losses | (97) | (171) |  |
Net Carrying Value | 824,637 | 891,738 |  |
CMBS |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Amortized Cost | 64,970 | 65,690 |  |
Gross Unrealized Gains | 0 | 0 |  |
Gross Unrealized Losses | (1,490) | (3,851) |  |
Fair Value | 63,480 | 61,839 |  |
Allowance for Credit Losses | 0 | 0 |  |
Net Carrying Value | $ 64,970 | $ 65,690 |  |

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