Income Taxes - Component of Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Expected tax expense, at U.S. federal statutory income tax rate of 21%	$ 4,600	$ 3,400
Rate differences on equity in earnings of Kronos, net of dividends	(1,900)	(1,000)
Nontaxable income		(600)
Nontaxable expenses		500
U.S. state income taxes and other, net		200
Income tax expense	$ 2,705	$ 2,505