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Equity (Schedule of Stock Offering Program) (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
At The Market Stock Offering [Line Items] |  |  |
Proceeds, net of fees (in millions) | $ 299.6 | $ 211.4 | $ 244.4
At The Market Program |  |  |
At The Market Stock Offering [Line Items] |  |  |
Number of shares issued | 12,525,215 | 8,459,430 | 8,422,498
Average price per share | $ 23.95 | $ 23.60 | $ 27.75
Proceeds, net of fees (in millions) | $ 288.1 | $ 196.5 | $ 229.1

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