Schedule II Condensed Financial Information of Registrant - Condensed Balance Sheet (Additional Information) (Details) - $ / shares	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 1996
Condensed Financial Statements, Captions [Line Items]
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001		$ 0.001
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000		1,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in usd per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	66,747,821	66,618,465
Treasury stock (in shares)	25,911,087	25,714,153
Parent company
Condensed Financial Statements, Captions [Line Items]
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	66,747,821	66,618,465
Treasury stock (in shares)	25,911,087	25,714,153