CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 13,871	$ (4,648)
Cumulative foreign translation adjustments	(10,103)	(713)
Unrealized losses on marketable securities, net of tax effects of $0 and ($48) during the three months ended December 31, 2016 and 2015	(11)	(119)
Actuarial gain, net of tax effects of $2 and ($2) during the three months ended December 31, 2016 and 2015	11	8
Total other comprehensive loss, net of tax	(10,103)	(824)
Comprehensive income (loss), net of tax	$ 3,768	$ (5,472)