Estimated Fair Value of Outstanding Debt Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Carrying Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt	$ 836,405	$ 858,755
Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt	744,720	870,794
3.95% Senior Notes Due 2028 | Carrying Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt	488,505	509,505
3.95% Senior Notes Due 2028 | Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt	431,556	511,652
5.15% Senior Notes Due 2029 | Carrying Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt	347,900	349,250
5.15% Senior Notes Due 2029 | Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total debt	$ 313,164	$ 359,142