Basic and Diluted Earnings per Share - Numerator and Denominator of the Basic and Diluted Per Share Computations for Earnings Attributable to Shareholders Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Net Earnings Attributable to Shareholders
Basic earnings attributable to shareholders	$ 287,220	$ 122,344
Diluted earnings attributable to shareholders	$ 287,220	$ 122,344
Weighted Average Shares
Weighted average basic shares outstanding	169,214	168,735
Effect of dilutive potential common shares	2,337	2,715
Weighted average diluted shares outstanding	171,551	171,450
Earnings Per Share
Basic earnings attributable to shareholders per share	$ 1.70	$ 0.73
Diluted earnings attributable to shareholders per share	$ 1.67	$ 0.71