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Environmental Matters - Additional Information (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2023 USD ($)
Site Contingency [Line Items]
Remediation costs	$ 5.6
Environmental Restoration Costs
Site Contingency [Line Items]
Estimated Costs Accrued For Remediation	$ 2.5
Maine | Environmental Restoration Costs
Site Contingency [Line Items]
Amortization period for environmental costs	5 years

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- Definition

Amount, before recovery, of expense for known and estimated future costs arising from requirement to perform environmental remediation.

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