Earnings Per Share - Calculation of Basic and Diluted Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net income	$ 93,644	$ 67,977
Weighted-average number of basic shares outstanding during the period	25,099	24,894
Dilutive effect of RSUs after application of treasury stock method	387	638
Weighted-average number of diluted shares outstanding during the period	25,486	25,532
Basic earnings per share	$ 3.73	$ 2.73
Diluted earnings per share	$ 3.67	$ 2.66