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Investment Securities Available for Sale - Amortized Cost And Estimated Fair Value By Contractual Maturity Of Investment Securities Available For Sale (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Amortized Cost |  |
Amortized cost, within one year | $ 24,566 |
Amortized cost, 1 to 5 years | 1,051,478 |
Amortized cost, 5 to 10 years | 439,954 |
Amortized cost, more than 10 years | 9,757,329 |
Amortized Cost | 11,273,327 | $ 10,991,506
Fair Value |  |
Fair value, within one year | 24,566 |
Fair value, 1 to 5 years | 981,495 |
Fair value, 5 to 10 years | 386,996 |
Fair value, more than 10 years | 8,285,046 |
Total fair value | 9,678,103 | 10,918,329
U.S. Treasury securities |  |
Amortized Cost |  |
Amortized cost, within one year | 24,293 |
Amortized cost, 1 to 5 years | 441,804 |
Amortized cost, 5 to 10 years | 49,856 |
Amortized cost, more than 10 years | 0 |
Amortized Cost | 515,953 | 120,465
Fair Value |  |
Fair value, within one year | 24,293 |
Fair value, 1 to 5 years | 407,430 |
Fair value, 5 to 10 years | 40,090 |
Fair value, more than 10 years | 0 |
Total fair value | 471,813 | 117,838
U.S. Government agency securities |  |
Amortized Cost |  |
Amortized cost, within one year | 273 |
Amortized cost, 1 to 5 years | 22,148 |
Amortized cost, 5 to 10 years | 29,990 |
Amortized cost, more than 10 years | 0 |
Amortized Cost | 52,411 | 53,214
Fair Value |  |
Fair value, within one year | 273 |
Fair value, 1 to 5 years | 19,588 |
Fair value, 5 to 10 years | 28,937 |
Fair value, more than 10 years | 0 |
Total fair value | 48,798 | 54,201
Mortgage-backed securities issued by U.S. Government agencies |  |
Amortized Cost |  |
Amortized cost, within one year | 0 |
Amortized cost, 1 to 5 years | 534 |
Amortized cost, 5 to 10 years | 4 |
Amortized cost, more than 10 years | 904,055 |
Amortized Cost | 904,593 | 790,329
Fair Value |  |
Fair value, within one year | 0 |
Fair value, 1 to 5 years | 517 |
Fair value, 5 to 10 years | 4 |
Fair value, more than 10 years | 792,228 |
Total fair value | 792,749 | 779,633
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Amortized Cost |  |
Amortized cost, within one year | 0 |
Amortized cost, 1 to 5 years | 4,659 |
Amortized cost, 5 to 10 years | 109,583 |
Amortized cost, more than 10 years | 8,030,132 |
Amortized Cost | 8,144,374 | 8,063,890
Fair Value |  |
Fair value, within one year | 0 |
Fair value, 1 to 5 years | 4,451 |
Fair value, 5 to 10 years | 102,400 |
Fair value, more than 10 years | 6,788,219 |
Total fair value | 6,895,070 | 8,012,301
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Amortized Cost |  |
Amortized cost, within one year | 0 |
Amortized cost, 1 to 5 years | 91 |
Amortized cost, 5 to 10 years | 12,293 |
Amortized cost, more than 10 years | 757,114 |
Amortized Cost | 769,498 | 951,691
Fair Value |  |
Fair value, within one year | 0 |
Fair value, 1 to 5 years | 88 |
Fair value, 5 to 10 years | 11,808 |
Fair value, more than 10 years | 643,231 |
Total fair value | 655,127 | 939,623
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Amortized Cost |  |
Amortized cost, within one year | 0 |
Amortized cost, 1 to 5 years | 573,334 |
Amortized cost, 5 to 10 years | 238,228 |
Amortized cost, more than 10 years | 66,028 |
Amortized Cost | 877,590 | 479,420
Fair Value |  |
Fair value, within one year | 0 |
Fair value, 1 to 5 years | 540,820 |
Fair value, 5 to 10 years | 203,757 |
Fair value, more than 10 years | 61,368 |
Total fair value | 805,945 | 481,744
Corporate debt securities and other debt securities |  |
Amortized Cost |  |
Amortized cost, within one year | 0 |
Amortized cost, 1 to 5 years | 8,908 |
Amortized cost, 5 to 10 years | 0 |
Amortized cost, more than 10 years | 0 |
Amortized Cost | 8,908 | 18,309
Fair Value |  |
Fair value, within one year | 0 |
Fair value, 1 to 5 years | 8,601 |
Fair value, 5 to 10 years | 0 |
Fair value, more than 10 years | 0 |
Total fair value | $ 8,601 | $ 18,801

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