Computation of Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net earnings	$ 24,638	$ 30,098	$ 79,489	$ 60,835
Numerator for basic income per share	24,638	30,098	79,489	60,835
Effect of dilutive securities:
Numerator for diluted income per share	$ 24,638	$ 32,618	$ 79,489	$ 60,835
Denominator:
Denominator for basic income per share - weighted average shares	63,612	62,427	63,539	62,491
Effect of dilutive securities:
Dilutive effect of common stock equivalents	2,089	2,624	2,305	2,633
Dilutive potential common shares	2,089	9,955	2,305	2,633
Denominator for diluted income per share	65,701	72,382	65,844	65,124
Net earnings per share:
Basic earnings per common share	$ 0.39	$ 0.48	$ 1.25	$ 0.97
Diluted earnings per common share	$ 0.38	$ 0.45	$ 1.21	$ 0.93
0.25% Convertible Senior Note Due 2022
Effect of dilutive securities:
Interest expense, net of tax, on 0.25% Convertible Senior Notes due 2022		$ 2,520
Effect of dilutive securities:
0.25% Convertible Senior Notes due 2022		7,331