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Deposits (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Deposits, by Type [Abstract] |  |  |
Non-interest bearing demand | $ 7,560,000 | $ 5,568,300 |
Interest bearing: |  |  |
Demand | 7,205,900 | 4,753,200 |
Savings | 8,379,300 | 4,981,600 |
Total | 438,000 | 186,700 |
Time, other | 1,490,400 | 779,800 |
Total interest bearing | 17,513,600 | 10,701,300 |
Total deposits | 25,073,600 | 16,269,600 |
Brokered time deposits | 0 |  |
Time deposits obtained through Certificate of Deposit Account Registry Service (CDARS) | 36,600 | 104,500 |
Time deposits of $250,000 or more | 438,000 | 186,700 |
FDIC deposit insurance limit | 250,000 |  |
Time, $250 and Over |  |  |
Due within 3 months or less | 47,800 |  |
Due after 3 months and within 6 months | 34,600 |  |
Due after 6 months and within 12 months | 283,900 |  |
Due within 2024 | 55,000 |  |
Due within 2025 | 10,700 |  |
Due within 2026 | 4,800 |  |
Due within 2027 and thereafter | 1,200 |  |
Total | 438,000 | 186,700 |
Total Time |  |  |
Due within 3 months or less | 311,800 |  |
Due after 3 months and within 6 months | 215,400 |  |
Due after 6 months and within 12 months | 1,005,400 |  |
Due within 2024 | 282,800 |  |
Due within 2025 | 69,200 |  |
Due within 2026 | 27,800 |  |
Due within 2027 and thereafter | 16,000 |  |
Total | 1,928,400 |  |
Interest expense, time deposits, $100,000 or more | $ 2,500 | $ 900 | $ 2,700

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