Income Taxes - Components of Income from Continuing Operations before Income Taxes and Noncontrolling Shareholders' Interests (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income From Continuing Operations Before Income Taxes And Noncontrolling Shareholders Interests [Line Items]
Income from continuing operations before income taxes and noncontrolling shareholders' interests	$ 46,056	$ 163,348	$ (6,525)	$ (11,976)	$ 44,317	$ 36,729	$ 15,109	$ 13,515	$ 190,903	$ 109,672	$ 114,058
United States
Income From Continuing Operations Before Income Taxes And Noncontrolling Shareholders Interests [Line Items]
Income from continuing operations before income taxes and noncontrolling shareholders' interests									161,885	(4,720)	108,838
Foreign
Income From Continuing Operations Before Income Taxes And Noncontrolling Shareholders Interests [Line Items]
Income from continuing operations before income taxes and noncontrolling shareholders' interests									$ 29,018	$ 114,392	$ 5,220