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Debt Securities - Additional Information (Details) $ in Thousands | Jun. 30, 2022 USD ($) security | Dec. 31, 2021 USD ($) security
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Available for Sale |  |
Debt securities with gross unrealized losses, fair value | $ | $ 2,629,923 | $ 2,783,177
Gross unrealized losses on debt securities | $ | $ 232,553 | $ 54,654
Ratio of gross unrealized losses to debt securities with gross unrealized losses | 8.80% | 2.00%
Count of debt securities | security | 1,177 | 1,252
Count of debt securities in an unrealized loss position | security | 881 | 373
Held to Maturity |  |
Debt securities with gross unrealized losses, fair value | $ | $ 876,737 |
Gross unrealized losses on debt securities | $ | $ 76,274 |
Ratio of gross unrealized losses to debt securities with gross unrealized losses | 8.70% |
Count of debt securities | security | 55 |
Count of debt securities in an unrealized loss position | security | 55 |
Total |  |
Debt securities with gross unrealized losses, fair value | $ | $ 3,506,660 | $ 2,783,177
Gross unrealized losses on debt securities | $ | $ 308,827 | $ 54,654
Ratio of gross unrealized losses to debt securities with gross unrealized losses | 8.80% | 2.00%
Count of debt securities | security | 1,232 | 1,252
Count of debt securities in an unrealized loss position | security | 936 | 373

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