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Investment Securities - Investments in Debt and Equity Securities Reported Less than Historical Cost (Details) - Investments reported at less than historical cost - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Schedule of Investments [Line Items] |  |
Historical cost | $ 2,271,810 | $ 658,858
Fair value | 2,022,665 | 645,218
Gross unrealized losses | $ 249,145 | $ 13,640
Percent of the Corporation's investments available for sale | 88.10% | 27.50%

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