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v3.23.2

Investment Securities Available for Sale (Schedule of Available for Sale Investment Securities) (Details) - USD ($) $ in Thousands | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 11,173,873 | $ 11,273,327
Gross Unrealized Gains | 508 | 2,560
Gross Unrealized Losses | (1,553,206) | (1,597,784)
Fair Value | 9,621,175 | 9,678,103
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 517,626 | 515,953
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (43,736) | (44,140)
Fair Value | 473,890 | 471,813
U.S. Government agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 52,397 | 52,411
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (3,794) | (3,613)
Fair Value | 48,603 | 48,798
Mortgage-backed securities issued by U.S. Government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 928,031 | 904,593
Gross Unrealized Gains | 0 | 1,624
Gross Unrealized Losses | (110,681) | (113,468)
Fair Value | 817,350 | 792,749
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 7,979,131 | 8,144,374
Gross Unrealized Gains | 508 | 936
Gross Unrealized Losses | (1,202,246) | (1,250,240)
Fair Value | 6,777,393 | 6,895,070
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 732,938 | 769,498
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (116,987) | (114,371)
Fair Value | 615,951 | 655,127
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 954,792 | 877,590
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (75,442) | (71,645)
Fair Value | 879,350 | 805,945
Corporate debt securities and other debt securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 8,958 | 8,908
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (320) | (307)
Fair Value | $ 8,638 | $ 8,601

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