Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment of Goodwill				$ 571.4	$ 1,119.6
ANS [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment of Goodwill	$ 46.4	$ 425.9	$ 1,119.6	$ 472.3	1,119.6
BDCC [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment of Goodwill	99.1	0.0
Discounted cash flow [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation technique				75.00%
Market approach [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation technique				25.00%
Non-Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment of Goodwill		$ 425.9			$ 1,119.6
Non-Recurring [Member] | ANS [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment of Goodwill	46.4
Non-Recurring [Member] | BDCC [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment of Goodwill	$ 99.1