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Investments (Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
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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