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Investment Securities - Schedule Of Unrealized Loss On Investments Securities Available for Sale (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | $ 1,947,515 | $ 409,725
Less than 12 months, gross unrealized losses | (14,241) | (2,666)
12 months or longer, fair value | 3,405,155 | 7,513,154
12 months or longer, gross unrealized losses | (520,697) | (1,331,466)
Total, fair value | 5,352,670 | 7,922,879
Total, gross unrealized losses | (534,938) | (1,334,132)
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 675,205 |
Less than 12 months, gross unrealized losses | (4,167) |
12 months or longer, fair value | 0 |
12 months or longer, gross unrealized losses | 0 |
Total, fair value | 675,205 |
Total, gross unrealized losses | (4,167) |
U.S. Government agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 0 | 0
Less than 12 months, gross unrealized losses | 0 | 0
12 months or longer, fair value | 28,844 | 28,940
12 months or longer, gross unrealized losses | (1,150) | (1,053)
Total, fair value | 28,844 | 28,940
Total, gross unrealized losses | (1,150) | (1,053)
Mortgage-backed securities issued by U.S. Government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 441,549 | 159,402
Less than 12 months, gross unrealized losses | (2,310) | (1,268)
12 months or longer, fair value | 673,891 | 565,358
12 months or longer, gross unrealized losses | (116,733) | (96,717)
Total, fair value | 1,115,440 | 724,760
Total, gross unrealized losses | (119,043) | (97,985)
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 127,603 | 215,917
Less than 12 months, gross unrealized losses | (3,143) | (1,193)
12 months or longer, fair value | 1,837,414 | 6,045,914
12 months or longer, gross unrealized losses | (253,793) | (1,093,019)
Total, fair value | 1,965,017 | 6,261,831
Total, gross unrealized losses | (256,936) | (1,094,212)
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 0 | 0
Less than 12 months, gross unrealized losses | 0 | 0
12 months or longer, fair value | 547,997 | 587,595
12 months or longer, gross unrealized losses | (111,709) | (104,892)
Total, fair value | 547,997 | 587,595
Total, gross unrealized losses | (111,709) | (104,892)
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 703,158 | 34,406
Less than 12 months, gross unrealized losses | (4,621) | (205)
12 months or longer, fair value | 308,126 | 276,675
12 months or longer, gross unrealized losses | (37,136) | (35,448)
Total, fair value | 1,011,284 | 311,081
Total, gross unrealized losses | (41,757) | (35,653)
Corporate debt securities and other debt securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 0 | 0
Less than 12 months, gross unrealized losses | 0 | 0
12 months or longer, fair value | 8,883 | 8,672
12 months or longer, gross unrealized losses | (176) | (337)
Total, fair value | 8,883 | 8,672
Total, gross unrealized losses | $ (176) | $ (337)

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