Marketable Securities - Schedule of Marketable Securities and Fair Value Measurements (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, current	$ 1.9	$ 56.1
Marketable securities, noncurrent	5.7	4.8
Fixed Income Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, current	1.9	56.1
Marketable securities, noncurrent	3.1	2.6
Mutual Fund
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, noncurrent	2.6	2.2
Quoted Prices in Active Markets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, noncurrent	2.6	2.2
Quoted Prices in Active Markets (Level 1) | Mutual Fund
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, noncurrent	2.6	2.2
Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, noncurrent	3.1	2.6
Significant Other Observable Inputs (Level 2) | Fixed Income Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities, current	1.9	56.1
Marketable securities, noncurrent	$ 3.1	$ 2.6