CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Net income	$ 10,816	$ 16,869	$ 34,992	$ 38,882
Other comprehensive income (loss):
Change in unrealized gain on available-for-sale securities (net of tax)		(11)		(17)
Foreign currency translations adjustments	(942)	(147)	(1,039)	156
Other comprehensive income (loss)	(942)	(158)	(1,039)	139
Total comprehensive income	$ 9,874	$ 16,711	$ 33,953	$ 39,021