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v3.23.1

Investment Securities, Equity Securities with Readily Determinable Fair Values and Other Investments (Details) - USD ($) | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
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 | 5,397,131,000 | 5,018,996,000
Estimated fair value, Available for sale securities | 4,859,818,000 | 4,417,796,000
Total Amortized cost | 5,397,131,000 | 5,018,996,000
Total Gross unrealized gains | 6,774,000 | 4,072,000
Total Gross unrealized losses | 544,087,000 | 605,272,000
Collateral Pledged |  |
Available-for-sale securities |  |
Amortized cost | 1,428,702,000 |
Estimated Fair Value |  |
Available-for-sale securities |  |
Available for sale debt securities and equity securities | 4,859,818,000 | 4,417,796,000
Reported Value Measurement |  |
Available-for-sale securities |  |
Available for sale debt securities and equity securities | 4,859,818,000 | 4,417,796,000
US Treasury Securities |  |
Available-for-sale securities |  |
Amortized cost | 49,967,000 | 49,752,000
Gross unrealized losses | (42,000) | (359,000)
US Treasury Securities | Estimated Fair Value |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 49,925,000 | 49,393,000
US Treasury Securities | Reported Value Measurement |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 49,925,000 | 49,393,000
Residential mortgage-backed securities |  |
Available-for-sale securities |  |
Amortized cost | 5,184,217,000 | 4,805,735,000
Gross unrealized gains | 5,289,000 | 3,145,000
Gross unrealized losses | (542,277,000) | (599,668,000)
Residential mortgage-backed securities | Estimated Fair Value |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 4,647,229,000 | 4,209,212,000
Residential mortgage-backed securities | Reported Value Measurement |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 4,647,229,000 | 4,209,212,000
US Government Corporations and Agencies Securities [Member] |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 810,907,000 | 681,121,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 3,836,322,000 | 3,528,091,000
States and political subdivisions |  |
Available-for-sale securities |  |
Amortized cost | 162,947,000 | 163,509,000
Gross unrealized gains | 1,485,000 | 927,000
Gross unrealized losses | (1,768,000) | (5,245,000)
States and political subdivisions | Estimated Fair Value |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 162,664,000 | 159,191,000
States and political subdivisions | Reported Value Measurement |  |
Available-for-sale securities |  |
Estimated fair value, Available for sale securities | 162,664,000 | 159,191,000
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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