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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020 | Dec. 31, 2008
--- | --- | --- | ---
Common stock, shares outstanding | 33,727,317 | 33,457,176 |
Common stock, shares issued | 33,727,317 | 33,457,176 |
Common Stock, Shares Held in Employee Trust, Shares | 107,397 | 105,067 |
kaleo [Member] |  |  |
Cost Method Investments, Original Cost |  |  | $ 7.5

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