CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (83,939)	$ 2,711	$ (88,587)	$ (23)
Cumulative foreign translation adjustments	5,740	(2,423)	5,027	(6,565)
Unrealized gain (loss) on marketable securities, net of tax effects of $(10) and ($58) during the three and six months ended March 31, 2016 and $(99) and $(75) during the three and six months ended March 31, 2015	16	267	(103)	202
Actuarial gain, net of tax effects of $2 and $0 during the three and six months ended March 31, 2016 and $3 and ($2) during the three and six months ended March 31, 2015	(5)	(13)	3	9
Total other comprehensive income (loss), net of tax	5,751	(2,169)	4,927	(6,354)
Comprehensive (loss) income, net of tax	$ (78,188)	$ 542	$ (83,660)	$ (6,377)