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Debt Securities - Additional Information (Details) $ in Thousands | Jun. 30, 2023 USD ($) security | Dec. 31, 2022 USD ($) security
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Available for Sale |  |
Debt securities with gross unrealized or unrecognized losses, fair value | $ | $ 2,265,057 | $ 2,439,533
Gross unrealized or unrecognized losses on debt securities | $ | $ 296,969 | $ 311,204
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses | 13.10% | 12.80%
Count of debt securities | security | 1,027 | 1,091
Count of debt securities in an unrealized or unrecognized loss position | security | 986 | 1,032
Held to Maturity |  |
Debt securities with gross unrealized or unrecognized losses, fair value | $ | $ 746,502 | $ 785,295
Gross unrealized or unrecognized losses on debt securities | $ | $ 147,600 | $ 133,017
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses | 19.80% | 16.90%
Count of debt securities | security | 55 | 55
Count of debt securities in an unrealized or unrecognized loss position | security | 55 | 55
Total |  |
Debt securities with gross unrealized or unrecognized losses, fair value | $ | $ 3,011,559 | $ 3,224,828
Gross unrealized or unrecognized losses on debt securities | $ | $ 444,569 | $ 444,221
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses | 14.80% | 13.80%
Count of debt securities | security | 1,082 | 1,146
Count of debt securities in an unrealized or unrecognized loss position | security | 1,041 | 1,087

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