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Investment Securities, Equity Securities with Readily Determinable Fair Values and Other Investments (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Held-to-maturity securities |  |
Amortized cost | $ 3,400,000 | $ 3,400,000
Estimated fair value | 3,400,000 | 3,400,000
Carrying Value | 3,400,000 | 3,400,000
Available-for-sale securities |  |
Amortized cost | 5,018,996,000 | 4,254,960,000
Gross unrealized gains | 4,072,000 | 17,197,000
Gross unrealized losses | (605,272,000) | (58,237,000)
Estimated fair value, Available for sale securities | 4,417,796,000 | 4,213,920,000
Total Amortized cost | 5,018,996,000 | 4,254,960,000
Available for sale debt securities and equity securities | 4,417,796,000 |
Collateral Pledged |  |
Available-for-sale securities |  |
Amortized cost | 1,562,832,000 |
Estimated Fair Value |  |
Available-for-sale securities |  |
Available for sale debt securities and equity securities | 4,417,796,000 | 4,213,920,000
Reported Value Measurement |  |
Available-for-sale securities |  |
Available for sale debt securities and equity securities | 4,417,796,000 | 4,213,920,000
US Treasury Securities |  |
Available-for-sale securities |  |
Amortized cost | 49,752,000 |
Gross unrealized losses | (359,000) |
US Treasury Securities | Estimated Fair Value |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 49,393,000 |
US Treasury Securities | Reported Value Measurement |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 49,393,000 |
Residential mortgage-backed securities |  |
Available-for-sale securities |  |
Amortized cost | 4,805,735,000 | 4,213,441,000
Gross unrealized gains | 3,145,000 | 14,159,000
Gross unrealized losses | (599,668,000) | (58,237,000)
Residential mortgage-backed securities | Estimated Fair Value |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 4,209,212,000 | 4,169,363,000
Residential mortgage-backed securities | Reported Value Measurement |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 4,209,212,000 | 4,169,363,000
US Government Corporations and Agencies Securities [Member] |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 681,121,000 | 824,474
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 3,528,091,000 | 3,344,889
States and political subdivisions |  |
Available-for-sale securities |  |
Amortized cost | 163,509,000 | 41,519,000
Gross unrealized gains | 927,000 | 3,038,000
Gross unrealized losses | (5,245,000) |
States and political subdivisions | Estimated Fair Value |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 159,191,000 | 44,557,000
States and political subdivisions | Reported Value Measurement |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 159,191,000 | 44,557,000
Other Debt Obligations |  |
Held-to-maturity securities |  |
Amortized cost | 3,400,000 | 3,400,000
Estimated fair value | 3,400,000 | 3,400,000
Carrying Value | $ 3,400,000 | $ 3,400,000

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