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v3.23.1

Investment Securities Available for Sale (Amortized Cost and Estimated Fair Value by Contractual Maturity of Investment Securities Available for Sale) (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Amortized Cost |  |
Within one year, amortized cost | $ 24,818 |
1 to 5 years, amortized cost | 1,080,485 |
5 to 10 years, amortized cost | 402,201 |
More than 10 years, amortized cost | 9,668,287 |
Amortized Cost | 11,175,791 | $ 11,273,327
Fair Value |  |
Within one year, fair value | 24,819 |
1 to 5 years, fair value | 1,021,472 |
5 to 10 years, fair value | 356,431 |
More than 10 years, fair value | 8,329,896 |
Total, fair value | 9,732,618 | 9,678,103
U.S. Treasury securities |  |
Amortized Cost |  |
Within one year, amortized cost | 24,560 |
1 to 5 years, amortized cost | 442,362 |
5 to 10 years, amortized cost | 49,860 |
More than 10 years, amortized cost | 0 |
Amortized Cost | 516,782 | 515,953
Fair Value |  |
Within one year, fair value | 24,560 |
1 to 5 years, fair value | 414,370 |
5 to 10 years, fair value | 41,350 |
More than 10 years, fair value | 0 |
Total, fair value | 480,280 | 471,813
U.S. Government agency securities |  |
Amortized Cost |  |
Within one year, amortized cost | 258 |
1 to 5 years, amortized cost | 22,148 |
5 to 10 years, amortized cost | 29,991 |
More than 10 years, amortized cost | 0 |
Amortized Cost | 52,397 | 52,411
Fair Value |  |
Within one year, fair value | 259 |
1 to 5 years, fair value | 19,841 |
5 to 10 years, fair value | 28,845 |
More than 10 years, fair value | 0 |
Total, fair value | 48,945 | 48,798
Mortgage-backed securities issued by U.S. Government agencies |  |
Amortized Cost |  |
Within one year, amortized cost | 0 |
1 to 5 years, amortized cost | 454 |
5 to 10 years, amortized cost | 4 |
More than 10 years, amortized cost | 809,584 |
Amortized Cost | 810,042 | 904,593
Fair Value |  |
Within one year, fair value | 0 |
1 to 5 years, fair value | 441 |
5 to 10 years, fair value | 4 |
More than 10 years, fair value | 708,100 |
Total, fair value | 708,545 | 792,749
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Amortized Cost |  |
Within one year, amortized cost | 0 |
1 to 5 years, amortized cost | 20,872 |
5 to 10 years, amortized cost | 87,576 |
More than 10 years, amortized cost | 8,051,382 |
Amortized Cost | 8,159,830 | 8,144,374
Fair Value |  |
Within one year, fair value | 0 |
1 to 5 years, fair value | 19,951 |
5 to 10 years, fair value | 82,013 |
More than 10 years, fair value | 6,923,536 |
Total, fair value | 7,025,500 | 6,895,070
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Amortized Cost |  |
Within one year, amortized cost | 0 |
1 to 5 years, amortized cost | 80 |
5 to 10 years, amortized cost | 11,932 |
More than 10 years, amortized cost | 741,865 |
Amortized Cost | 753,877 | 769,498
Fair Value |  |
Within one year, fair value | 0 |
1 to 5 years, fair value | 77 |
5 to 10 years, fair value | 11,605 |
More than 10 years, fair value | 636,877 |
Total, fair value | 648,559 | 655,127
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Amortized Cost |  |
Within one year, amortized cost | 0 |
1 to 5 years, amortized cost | 585,636 |
5 to 10 years, amortized cost | 222,838 |
More than 10 years, amortized cost | 65,456 |
Amortized Cost | 873,930 | 877,590
Fair Value |  |
Within one year, fair value | 0 |
1 to 5 years, fair value | 558,026 |
5 to 10 years, fair value | 192,614 |
More than 10 years, fair value | 61,383 |
Total, fair value | 812,023 | 805,945
Corporate debt securities and other debt securities |  |
Amortized Cost |  |
Within one year, amortized cost | 0 |
1 to 5 years, amortized cost | 8,933 |
5 to 10 years, amortized cost | 0 |
More than 10 years, amortized cost | 0 |
Amortized Cost | 8,933 | 8,908
Fair Value |  |
Within one year, fair value | 0 |
1 to 5 years, fair value | 8,766 |
5 to 10 years, fair value | 0 |
More than 10 years, fair value | 0 |
Total, fair value | $ 8,766 | $ 8,601

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