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Investment Securities -Schedule of Investment Securities Available-for-sale (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 1,716,218 | $ 964,389
Gross Unrealized Gains | 17,200 | 867
Gross Unrealized Losses | 44,650 | 70,222
Estimated Fair Value | 1,688,768 | 895,034
GSE debentures |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 185,449 | 195,099
Gross Unrealized Gains | 512 | 225
Gross Unrealized Losses | 12,284 | 19,030
Estimated Fair Value | 173,677 | 176,294
GSE CMOs |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 500,446 | 62,567
Gross Unrealized Gains | 2,784 | 4
Gross Unrealized Losses | 6,660 | 7,028
Estimated Fair Value | 496,570 | 55,543
GSE MBSs |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 334,476 | 166,843
Gross Unrealized Gains | 3,009 | 63
Gross Unrealized Losses | 11,740 | 18,621
Estimated Fair Value | 325,745 | 148,285
Municipal obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 231,924 | 20,526
Gross Unrealized Gains | 8,305 | 19
Gross Unrealized Losses | 13 | 291
Estimated Fair Value | 240,216 | 20,254
Corporate debt obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 39,209 | 12,140
Gross Unrealized Gains | 863 | 225
Gross Unrealized Losses | 49 | 78
Estimated Fair Value | 40,023 | 12,287
U.S. Treasury bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 424,214 | 506,714
Gross Unrealized Gains | 1,727 | 331
Gross Unrealized Losses | 13,904 | 25,173
Estimated Fair Value | 412,037 | 481,872
Foreign government obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 500 | 500
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 1
Estimated Fair Value | $ 500 | $ 499

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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