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Investment Securities - Investment in MediaAlpha textual (Details) - Marketing Technology (MediaAlpha) - USD ($) $ / shares in Units, $ in Millions | Jun. 30, 2021 | Dec. 31, 2020
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Subsidiary, Sale of Stock [Line Items] |  |
Share price (in usd per share) | $ 42.10 | $ 39.07
Investment owned, balance | $ 713.2 | $ 802.2

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- Details
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