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Other, Net (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Other, Net [Abstract] |  |  |  |
Interest income | $ 0.7 | $ 1.4 | $ 1.6 | $ 3.1
AFUDC equity | 3.4 | 1.4 | 4.9 | 3.1
Pension and other postretirement non-service benefit | 8.6 | 3.1 | 17.1 | 5.8
Miscellaneous | (0.3) | 0.6 | (0.7) | (0.1)
Other, net | $ 12.4 | $ 6.5 | $ 22.9 | $ 11.9

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