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Financings and Capitalization (Forward Stock Contracts) (Details) - $ / shares | Mar. 31, 2021 | Dec. 22, 2020 | Sep. 15, 2020
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Forward Contracts Entered Into September 15, 2020 And Maturing June 30, 2022 |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Number of Shares |  |  | 846,759
Initial forward price (in dollars per share) | $ 60.01 |  | $ 61.04
Forward Contracts Entered Into December 22, 2020 And Maturing June 22, 2022 |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Number of Shares |  | 115,595 |
Initial forward price (in dollars per share) | $ 61.31 | $ 61.81 |

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