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Investment Securities - Schedule of Investment Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
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Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | $ 82,959 | $ 117,451
Less than twelve months, unrealized losses | 514 | 1,343
Twelve months or longer, estimated fair value | 469,963 | 587,823
Twelve months or longer, unrealized losses | 44,136 | 68,879
Total, estimated fair value | 552,922 | 705,274
Total, unrealized losses | 44,650 | 70,222
Total temporarily impaired investment securities |  |
Less than twelve months, estimated fair value | 82,959 | 117,451
Less than twelve months, unrealized losses | 514 | 1,343
Twelve months or longer, estimated fair value | 469,963 | 587,823
Twelve months or longer, unrealized losses | 44,136 | 68,879
Total, estimated fair value | 552,922 | 705,274
Total, unrealized losses | 44,650 | 70,222
GSE debentures |  |
Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | 32 | 30,753
Less than twelve months, unrealized losses | 1 | 281
Twelve months or longer, estimated fair value | 103,884 | 107,750
Twelve months or longer, unrealized losses | 12,283 | 18,749
Total, estimated fair value | 103,916 | 138,503
Total, unrealized losses | 12,284 | 19,030
GSE CMOs |  |
Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | 68,184 | 4,664
Less than twelve months, unrealized losses | 460 | 107
Twelve months or longer, estimated fair value | 45,145 | 50,334
Twelve months or longer, unrealized losses | 6,200 | 6,921
Total, estimated fair value | 113,329 | 54,998
Total, unrealized losses | 6,660 | 7,028
GSE MBSs |  |
Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | 79 | 11,128
Less than twelve months, unrealized losses | 1 | 596
Twelve months or longer, estimated fair value | 114,594 | 131,481
Twelve months or longer, unrealized losses | 11,739 | 18,025
Total, estimated fair value | 114,673 | 142,609
Total, unrealized losses | 11,740 | 18,621
Municipal obligations |  |
Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | 9,721 | 3,616
Less than twelve months, unrealized losses | 11 | 74
Twelve months or longer, estimated fair value | 391 | 3,568
Twelve months or longer, unrealized losses | 2 | 217
Total, estimated fair value | 10,112 | 7,184
Total, unrealized losses | 13 | 291
Corporate debt obligations |  |
Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | 4,943 | 0
Less than twelve months, unrealized losses | 41 | 0
Twelve months or longer, estimated fair value | 2,666 | 2,550
Twelve months or longer, unrealized losses | 8 | 78
Total, estimated fair value | 7,609 | 2,550
Total, unrealized losses | 49 | 78
U.S. Treasury bonds |  |
Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | 0 | 67,290
Less than twelve months, unrealized losses | 0 | 285
Twelve months or longer, estimated fair value | 203,283 | 291,641
Twelve months or longer, unrealized losses | 13,904 | 24,888
Total, estimated fair value | 203,283 | 358,931
Total, unrealized losses | 13,904 | 25,173
Foreign government obligations |  |
Investment securities available-for-sale: |  |
Less than twelve months, estimated fair value | 0 | 0
Less than twelve months, unrealized losses | 0 | 0
Twelve months or longer, estimated fair value | 0 | 499
Twelve months or longer, unrealized losses | 0 | 1
Total, estimated fair value | 0 | 499
Total, unrealized losses | $ 0 | $ 1

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