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Investment Securities Available for Sale - Schedule Of Unrealized Loss On Investments (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | $ 2,523,310 | $ 6,596,065
Less than 12 months, gross unrealized losses | (173,930) | (96,227)
12 months or longer, fair value | 6,989,855 | 1,523,383
12 months or longer, gross unrealized losses | (1,423,854) | (43,377)
Total, fair value | 9,513,165 | 8,119,448
Total, gross unrealized losses | (1,597,784) | (139,604)
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 139,737 | 49,648
Less than 12 months, gross unrealized losses | (6,789) | (379)
12 months or longer, fair value | 307,582 | 47,590
12 months or longer, gross unrealized losses | (37,351) | (2,248)
Total, fair value | 447,319 | 97,238
Total, gross unrealized losses | (44,140) | (2,627)
U.S. Government agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 28,938 | 21,760
Less than 12 months, gross unrealized losses | (1,053) | (387)
12 months or longer, fair value | 19,603 | 0
12 months or longer, gross unrealized losses | (2,560) | 0
Total, fair value | 48,541 | 21,760
Total, gross unrealized losses | (3,613) | (387)
Mortgage-backed securities issued by U.S. Government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 187,655 | 461,078
Less than 12 months, gross unrealized losses | (5,952) | (5,858)
12 months or longer, fair value | 521,395 | 244,264
12 months or longer, gross unrealized losses | (107,516) | (5,606)
Total, fair value | 709,050 | 705,342
Total, gross unrealized losses | (113,468) | (11,464)
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 1,473,348 | 5,729,476
Less than 12 months, gross unrealized losses | (120,135) | (82,671)
12 months or longer, fair value | 5,365,233 | 643,758
12 months or longer, gross unrealized losses | (1,130,105) | (19,409)
Total, fair value | 6,838,581 | 6,373,234
Total, gross unrealized losses | (1,250,240) | (102,080)
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 | 119,649 | 187,431
Less than 12 months, gross unrealized losses | (10,311) | (3,981)
12 months or longer, fair value | 535,478 | 504,238
12 months or longer, gross unrealized losses | (104,060) | (12,745)
Total, fair value | 655,127 | 691,669
Total, gross unrealized losses | (114,371) | (16,726)
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 | 565,382 | 146,672
Less than 12 months, gross unrealized losses | (29,383) | (2,951)
12 months or longer, fair value | 240,564 | 83,533
12 months or longer, gross unrealized losses | (42,262) | (3,369)
Total, fair value | 805,946 | 230,205
Total, gross unrealized losses | (71,645) | $ (6,320)
Corporate debt securities and other debt securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 8,601 |
Less than 12 months, gross unrealized losses | (307) |
12 months or longer, fair value | 0 |
12 months or longer, gross unrealized losses | 0 |
Total, fair value | 8,601 |
Total, gross unrealized losses | $ (307) |

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