Stockholders' Equity and Earnings Per Common Share - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Oct. 31, 2023	Feb. 21, 2023	Dec. 01, 2022
Outstanding Restricted Stock and Stock Success Unit Grant Prices Lower Limit		$ 18.78		$ 18.78
Outstanding Restricted Stock and Stock Success Unit Grant Prices Upper Limit		$ 49.29		$ 49.29
Antidilutive Securities Excluded from Computation of Earnings Per Share				400,000	100,000
Cost of Shares Repurchased	[1]	$ 74.8	$ 42.6	$ 175.4	$ 137.5
Number of Treasury Shares Repurchased		1,500,000	1,200,000	3,900,000	4,200,000
Authorized Shares of Preferred Stock		25,000,000.0		25,000,000.0
Par Value Per Share of Preferred Stock		$ 0.10		$ 0.10
Issued Shares of Preferred Stock		0		0
Repurchase Program Authorized in December 2022
Authorized Amount of Treasury Share Repurchases Under Stock Repurchase Program								$ 200.0
Repurchase Program Authorized in February 2023
Authorized Amount of Treasury Share Repurchases Under Stock Repurchase Program							$ 250.0
Remaining Amount of Treasury Share Repurchases Authorized Under Stock Repurchase Program		$ 75.9		$ 75.9
Repurchase Program Authorized in October 2023 | Subsequent Event
Authorized Amount of Treasury Share Repurchases Under Stock Repurchase Program						$ 500.0

[1] 1Includes a de minimis amount and $0.1 million of commissions for the three and nine months ended September 30, 2023, respectively, and a de minimis amount and $0.1 million of commissions for the three and nine months ended September 30, 2022, respectively. There was $0.7 million and $1.2 million of excise tax for the three and nine months ended September 30, 2023, respectively. There were no excise taxes during the three and nine months ended September 30, 2022.