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Investment Securities, Equity Securities with Readily Determinable Fair Values and Other Investments (Contractual Maturities and Estimated Fair Values) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Amortized Cost |  |  |
Due in one year or less, held-to-maturity debt securities amortized cost | $ 2,075,000 |  |
Due after one year through five years, held-to-maturity debt securities amortized cost | 1,325,000 |  |
Amortized cost, held-to-maturity debt securities | 3,400,000 | $ 3,400,000 |
Fair Value |  |  |
Due in one year or less, held-to-maturity debt securities, Estimated fair value | 2,075,000 |  |
Due after one year through five years, held-to-maturity debt securities, Estimated fair value | 1,325,000 |  |
Estimated fair value | 3,400,000 | 3,400,000 |
Available-for-sale debt securities amortized cost disclosures |  |  |
Due after five years through ten years, available-for-sale debt securities amortized cost | 440,000 |  |
Due after ten years, available-for-sale debt securities amortized cost | 160,561,000 |  |
Residential mortgage-backed securities, amortized cost | 5,169,813,000 |  |
Amortized cost, Available-for-sale securities | 5,330,814,000 | 5,018,996,000 |
Available for sale debt securities, Estimated Fair Value Disclosures |  |  |
Due after five years through ten years, available-for-sale debt securities, Estimated Fair Value | 440,000 |  |
Due after ten years, available-for-sale debt securities, Estimated Fair Value | 161,802,000 |  |
Residential mortgage-backed securities, Estimated Fair Value | 4,660,099,000 |  |
Estimated fair value, Available for sale securities | 4,822,341,000 | 4,417,796,000 |
Available for sale debt securities, Estimated Fair Value Disclosures |  |  |
Proceeds from sales and calls of available for sale securities | 2,045,000 | 800,000 | $ 5,890,000
Proceeds from sales and calls of available for sale securities | 2,045,000 | 800,000 | 5,890,000
Proceeds from sales of mortgage-backed securities | 0 | 0 | 0
Gross gains realized on sales | 0 | 0 | 0
Gross losses realized on sales | 3,000 | $ 0 | $ 16,000
Collateral Pledged |  |  |
Available-for-sale debt securities amortized cost disclosures |  |  |
Amortized cost, Available-for-sale securities | 1,836,634,000 |  |
Available for sale debt securities, Estimated Fair Value Disclosures |  |  |
Fair value of available for sale investment securities pledged | $ 1,598,853,000 |  |

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