Discontinued Operations - Additional Information (Details) - Discontinued Operations, Disposed of by Sale - Fairbanks Morse - USD ($) $ in Millions		3 Months Ended
Jan. 21, 2020	Mar. 31, 2020	Mar. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of investment projects	$ 450.0
The pre-tax gain on the disposition	274.3
Gain from sale of discontinued operations, net of tax	$ 209.7	$ 209.7	$ 0.0

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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