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Investment Securities (Schedule of Investment Securities Portfolio Continuous Unrealized Loss Position) (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | $ 1,328,178,000 | $ 814,324,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (105,511,000) | (17,916,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 1,774,421,000 | 267,739,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (421,617,000) | (10,754,000)
Total, fair value | 3,102,599,000 | 1,082,063,000
Total, unrealized losses | (527,128,000) | (28,670,000)
Subprime mortgage-backed available-for-sale securities | 3,243,017,000 | 2,327,793,000
U.S. Treasury |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 0 | 0
Continuous unrealized losses existing for less than 12 months, unrealized losses | 0 | 0
Continuous unrealized losses existing for greater than 12 months, fair value | 0 | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | 0 | 0
Total, fair value | 0 | 0
Total, unrealized losses | 0 | 0
Subprime mortgage-backed available-for-sale securities | 14,948,000 | 0
U.S. government agencies |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 36,750,000 | 0
Continuous unrealized losses existing for less than 12 months, unrealized losses | (3,250,000) | 0
Continuous unrealized losses existing for greater than 12 months, fair value | 7,436,000 | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (2,564,000) | 0
Total, fair value | 44,186,000 | 0
Total, unrealized losses | (5,814,000) | 0
Subprime mortgage-backed available-for-sale securities | 74,222,000 | 52,507,000
Municipal |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 88,433,000 | 47,726,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (1,997,000) | (200,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 41,642,000 | 850,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (3,439,000) | (17,000)
Total, fair value | 130,075,000 | 48,576,000
Total, unrealized losses | (5,436,000) | (217,000)
Subprime mortgage-backed available-for-sale securities | 168,655,000 | 165,594,000
Financial issuers |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 14,420,000 | 23,855,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (580,000) | (1,145,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 70,283,000 | 45,539,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (8,711,000) | (1,454,000)
Total, fair value | 84,703,000 | 69,394,000
Total, unrealized losses | (9,291,000) | (2,599,000)
Subprime mortgage-backed available-for-sale securities | 84,703,000 | 94,697,000
Other |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 0 | 0
Continuous unrealized losses existing for less than 12 months, unrealized losses | 0 | 0
Continuous unrealized losses existing for greater than 12 months, fair value | 0 | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | 0 | 0
Total, fair value | 0 | 0
Total, unrealized losses | 0 | 0
Subprime mortgage-backed available-for-sale securities | 1,002,000 | 1,007,000
Mortgage-backed securities |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 1,185,885,000 | 742,743,000
Continuous unrealized losses existing for less than 12 months, unrealized losses | (99,494,000) | (16,571,000)
Continuous unrealized losses existing for greater than 12 months, fair value | 1,578,200,000 | 221,350,000
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (389,301,000) | (9,283,000)
Total, fair value | 2,764,085,000 | 964,093,000
Total, unrealized losses | (488,795,000) | (25,854,000)
Subprime mortgage-backed available-for-sale securities | 2,819,937,000 | 1,907,981,000
Collateralized mortgage obligations |  |
Available-for-sale securities |  |
Continuous unrealized losses existing for less than 12 months, fair value | 2,690,000 | 0
Continuous unrealized losses existing for less than 12 months, unrealized losses | (190,000) | 0
Continuous unrealized losses existing for greater than 12 months, fair value | 76,860,000 | 0
Continuous unrealized losses existing for greater than 12 months, unrealized losses | (17,602,000) | 0
Total, fair value | 79,550,000 | 0
Total, unrealized losses | (17,792,000) | 0
Mortgage-backed securities, subprime |  |
Available-for-sale securities |  |
Subprime mortgage-backed available-for-sale securities | $ 0 | $ 0

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