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Investment Securities - Investment in MediaAlpha (Details) - MediaAlpha - USD ($) $ / shares in Units, $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
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Investment securities |  |
Share price (in USD per share) | $ 15.44 | $ 39.07
Investment owned, balance | $ 261.6 | $ 802.2

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- Details
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