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Commitments and Contingencies - Additional Information (Detail) - Environmental Matters $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) facility	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Contingencies And Commitments [Line Items]
Pretax charge to comply U.S. federal, state and local environmental control and protection regulations	$ 17.5	$ 16.3	$ 15.9
Capital expenditure to comply environmental regulations	3.1	1.2	$ 1.4
Environmental reserves	102.4	91.3
Environmental reserves included in current liabilities	$ 9.8	7.1
Nuclear Operations Group
Contingencies And Commitments [Line Items]
Number of facilities | facility	2
Financial assurance to pay expected cost of decommissioning	$ 61.8
Nuclear Energy Group
Contingencies And Commitments [Line Items]
Financial assurance to pay expected cost of decommissioning	$ 46.4	$ 47.9

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Number of former nuclear fuel processing facilities.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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