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Investments (Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
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Unconsolidated Subsidiaries |  |
Investment in unconsolidated subsidiaries | $ 317,869 | $ 310,529
Qualified affordable housing project tax credit partnerships |  |
Unconsolidated Subsidiaries |  |
Investment in unconsolidated subsidiaries | 15,980 | 27,719
All other investments, primarily investment fund LPs/LLCs |  |
Unconsolidated Subsidiaries |  |
Investment in unconsolidated subsidiaries | $ 301,889 | $ 282,810

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