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Other, Net (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Other, Net [Abstract] |  |  |  |
Interest income | $ 1.1 | $ 1.3 | $ 2.7 | $ 4.4
AFUDC equity | 3.5 | 1.8 | 8.4 | 4.9
Pension and other postretirement non-service benefit | 9.3 | 0.6 | 26.4 | 6.4
Sale of emission reduction credits | 0.0 | 4.6 | 0.0 | 4.6
Miscellaneous | 0.4 | (0.3) | (0.3) | (0.4)
Other, net | $ 14.3 | $ 8.0 | $ 37.2 | $ 19.9

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