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Convertible Securities (Details) - Junior Convertible Trust Preferred Securities | Aug. 10, 2018 USD ($) $ / shares | Aug. 09, 2018 | Sep. 30, 2018
--- | --- | --- | ---
Debt Instrument, Redemption [Line Items] |  |  |
Stated interest rate |  |  | 5.15%
Conversion ratio per share of common stock | 0.2525 | 0.2500 |
Face amount of convertible security | $ | $ 50.00 |  |
Adjusted conversion price (in dollars per share) | $ / shares | $ 198.02 |  |

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