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Investment Securities Available for Sale - Schedule Of Unrealized Loss On Investments (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | $ 6,596,065 | $ 1,379,662
Less than 12 months, gross unrealized losses | (96,227) | (16,669)
12 months or longer, fair value | 1,523,383 | 0
12 months or longer, gross unrealized losses | (43,377) | 0
Total, fair value | 8,119,448 | 1,379,662
Total, gross unrealized losses | (139,604) | (16,669)
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 49,648 |
Less than 12 months, gross unrealized losses | (379) |
12 months or longer, fair value | 47,590 |
12 months or longer, gross unrealized losses | (2,248) |
Total, fair value | 97,238 |
Total, gross unrealized losses | (2,627) |
U.S. Government agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 21,760 |
Less than 12 months, gross unrealized losses | (387) |
12 months or longer, fair value | 0 |
12 months or longer, gross unrealized losses | 0 |
Total, fair value | 21,760 |
Total, gross unrealized losses | (387) |
Mortgage-backed securities issued by U.S. Government agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 461,078 | 566,896
Less than 12 months, gross unrealized losses | (5,858) | (5,925)
12 months or longer, fair value | 244,264 | 0
12 months or longer, gross unrealized losses | (5,606) | 0
Total, fair value | 705,342 | 566,896
Total, gross unrealized losses | (11,464) | (5,925)
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value | 5,729,476 |
Less than 12 months, gross unrealized losses | (82,671) |
12 months or longer, fair value | 643,758 |
12 months or longer, gross unrealized losses | (19,409) |
Total, fair value | 6,373,234 |
Total, gross unrealized losses | (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 | 187,431 | 803,429
Less than 12 months, gross unrealized losses | (3,981) | (10,576)
12 months or longer, fair value | 504,238 | 0
12 months or longer, gross unrealized losses | (12,745) | 0
Total, fair value | 691,669 | 803,429
Total, gross unrealized losses | (16,726) | (10,576)
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 | 146,672 |
Less than 12 months, gross unrealized losses | (2,951) |
12 months or longer, fair value | 83,533 |
12 months or longer, gross unrealized losses | (3,369) |
Total, fair value | 230,205 |
Total, gross unrealized losses | $ (6,320) |
Corporate debt securities and other debt securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 months, fair value |  | 9,337
Less than 12 months, gross unrealized losses |  | (168)
12 months or longer, fair value |  | 0
12 months or longer, gross unrealized losses |  | 0
Total, fair value |  | 9,337
Total, gross unrealized losses |  | $ (168)

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