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Debt Securities - Additional Information (Details) $ in Thousands | Mar. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) security
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Available for Sale |  |
Debt securities with gross unrealized losses, fair value | $ | $ 2,593,774 | $ 2,783,177
Gross unrealized losses on debt securities | $ | $ 139,329 | $ 54,654
Ratio of gross unrealized losses to debt securities with gross unrealized losses | 5.40% | 2.00%
Count of debt securities | security | 1,185 | 1,252
Count of debt securities in an unrealized loss position | security | 645 | 373
Held to Maturity |  |
Debt securities with gross unrealized losses, fair value | $ | $ 942,846 |
Gross unrealized losses on debt securities | $ | $ 33,235 |
Ratio of gross unrealized losses to debt securities with gross unrealized losses | 3.50% |
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 | $ | $ 3,536,620 | $ 2,783,177
Gross unrealized losses on debt securities | $ | $ 172,564 | $ 54,654
Ratio of gross unrealized losses to debt securities with gross unrealized losses | 4.90% | 2.00%
Count of debt securities | security | 1,240 | 1,252
Count of debt securities in an unrealized loss position | security | 700 | 373

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