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		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Net Earnings Attributable to Shareholders
Basic earnings attributable to shareholders	$ 316,372	$ 183,869	$ 603,592	$ 306,213
Diluted earnings attributable to shareholders	$ 316,372	$ 183,869	$ 603,592	$ 306,213
Weighted Average Shares
Weighted average basic shares outstanding	169,210	166,767	169,140	167,751
Effect of dilutive potential common shares	2,467	2,523	2,520	2,631
Weighted average diluted shares outstanding	171,677	169,290	171,660	170,382
Earnings Per Share
Basic earnings attributable to shareholders per share	$ 1.87	$ 1.10	$ 3.57	$ 1.83
Diluted earnings attributable to shareholders per share	$ 1.84	$ 1.09	$ 3.52	$ 1.80