Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 9,596	$ 23,903	$ 30,737	$ 40,197
Other comprehensive income (loss):
Foreign currency translation adjustments	4,085	(14,565)	15,182	(15,147)
Amortization of net actuarial gains and losses, net of taxes of $9 and $32 for the three and six months ended December 31, 2017, respectively, and $137 and $85 for the three and six months ended December 31, 2016, respectively	36	424	118	312
Comprehensive income	$ 13,717	$ 9,762	$ 46,037	$ 25,362