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Deposits (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Deposits, by Type [Abstract] |  |  |
Non-interest bearing demand | $ 6,029,600 | $ 7,560,000 |
Interest bearing: |  |  |
Demand | 6,507,800 | 7,205,900 |
Savings | 7,775,800 | 8,379,300 |
Total | 811,600 | 438,000 |
Time, other | 2,198,300 | 1,490,400 |
Total interest bearing | 17,293,500 | 17,513,600 |
Total deposits | 23,323,100 | 25,073,600 |
Brokered time deposits | 0 |  |
Time deposits obtained through Certificate of Deposit Account Registry Service (CDARS) | 26,600 | 36,600 |
Time deposits of $250,000 or more | 811,600 | 438,000 |
FDIC deposit insurance limit | 250,000 |  |
Time, $250 and Over |  |  |
Due within 3 months or less | 219,700 |  |
Due after 3 months and within 6 months | 233,900 |  |
Due after 6 months and within 12 months | 279,500 |  |
Due within 2025 | 62,800 |  |
Due within 2026 | 9,100 |  |
Due within 2027 | 4,900 |  |
Due within 2028 and thereafter | 1,700 |  |
Total | 811,600 | 438,000 |
Total Time |  |  |
Due within 3 months or less | 770,400 |  |
Due after 3 months and within 6 months | 854,000 |  |
Due after 6 months and within 12 months | 1,024,300 |  |
Due within 2025 | 277,100 |  |
Due within 2026 | 48,200 |  |
Due within 2027 | 28,400 |  |
Due within 2028 and thereafter | 7,500 |  |
Total | 3,009,900 |  |
Interest expense, time deposits, $100,000 or more | $ 21,500 | $ 2,500 | $ 900

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- Definition Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing after twelve months from the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Industry Guide -Number 3 -Section V -Paragraph D-E -Publisher SEC + Details
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- Definition Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three months or fewer from the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Industry Guide -Number 3 -Section V -Paragraph D-E -Publisher SEC + Details
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- Definition The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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