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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
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Amortized Cost |  |  |
Due in one year or less, held-to-maturity debt securities amortized cost | $ 1,200,000 |  |
Due after one year through five years, held-to-maturity debt securities amortized cost | 2,200,000 |  |
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 | 1,200,000 |  |
Due after one year through five years, held-to-maturity debt securities, Estimated fair value | 2,200,000 |  |
Estimated fair value | 3,400,000 | 3,400,000 |
Available-for-sale debt securities amortized cost disclosures |  |  |
Due in one year or less, available-for-sale debt securities amortized cost | 49,752,000 |  |
Due after ten years, available-for-sale debt securities amortized cost | 163,509,000 |  |
Residential mortgage-backed securities, amortized cost | 4,805,735,000 |  |
Amortized cost, Available for sale securities | 5,018,996,000 | 4,254,960,000 |
Available for sale debt securities, Estimated Fair Value Disclosures |  |  |
Due in one year or less, available-for-sale debt securities, Estimated Fair Value | 49,393,000 |  |
Due after ten years, available-for-sale debt securities, Estimated Fair Value | 159,191,000 |  |
Residential mortgage-backed securities, Estimated Fair Value | 4,209,212,000 |  |
Estimated fair value, Available for sale securities | 4,417,796,000 |  |
Available for sale debt securities, Estimated Fair Value Disclosures |  |  |
Proceeds from sales and calls of available for sale securities | 800,000 | 5,890,000 | $ 42,350,000
Proceeds from sales of mortgage-backed securities | 0 | 0 | 0
Gross gains realized on sales | 0 | 0 | 1,000
Gross losses realized on sales | 0 | $ 16,000 | $ 6,000
Collateral Pledged |  |  |
Available for sale debt securities, Estimated Fair Value Disclosures |  |  |
Fair value of available for sale investment securities pledged | $ 1,323,081,000 |  |

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after rolling tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27198-111563 + Details
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