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Debt and Financing Arrangements - Classification of the Company Lease Obligations (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Operating Lease Obligations:
Operating Lease Obligations	$ 1.8	$ 1.9
Operating Lease Obligations (current portion)	Liabilities, Current	Liabilities, Current
Operating Lease Obligations	$ 4.9	$ 3.7
Operating Lease Obligations (long-term portion)	Liabilities, Noncurrent	Liabilities, Noncurrent
Total Operating Lease Obligations	$ 6.7	$ 5.6
Capital Lease Obligations:
Other Current Liabilities (current portion)	$ 0.1	$ 0.1
Other Current Liabilities (current portion)	Other Liabilities, Current	Other Liabilities, Current
Other Noncurrent Liabilities (long-term portion)	$ 0.4	$ 0.4
Other Noncurrent Liabilities (long-term portion)	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Total Capital Lease Obligations	$ 0.5	$ 0.5
Total Lease Obligations	7.2	$ 6.1
Lease Obligations [Member]
Operating Lease Obligations:
Total Operating Lease Obligations	$ 6,677.0

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